They're homemade from "events" and "games" respectively. I manually, using bbref, found the dates of the last regular season games, then did this:
Step 1: Duplicate events and games exactly as-is, naming them events_regseason and games_regseason (or whatever you want, just keep track throughout)
DELETE from games_regseason
where (substring(game_id,4,4)="1974" AND substring(game_id,4,8)>="19741003");
DELETE from games_regseason
where (substring(game_id,4,4)="1975" AND substring(game_id,4,8)>="19751001");
DELETE from games_regseason
where (substring(game_id,4,4)="1976" AND substring(game_id,4,8)>="19761005");
DELETE from games_regseason
where (substring(game_id,4,4)="1977" AND substring(game_id,4,8)>="19771004");
DELETE from games_regseason
where (substring(game_id,4,4)="1978" AND substring(game_id,4,8)>="19781003");
DELETE from games_regseason
where (substring(game_id,4,4)="1979" AND substring(game_id,4,8)>="19791002");
DELETE from games_regseason
where (substring(game_id,4,4)="1980" AND substring(game_id,4,8)>="19801006");
DELETE from games_regseason
where (substring(game_id,4,4)="1981" AND substring(game_id,4,8)>="19811005");
DELETE from games_regseason
where (substring(game_id,4,4)="1982" AND substring(game_id,4,8)>="19821005");
DELETE from games_regseason
where (substring(game_id,4,4)="1983" AND substring(game_id,4,8)>="19831004");
DELETE from games_regseason
where (substring(game_id,4,4)="1984" AND substring(game_id,4,8)>="19841002");
DELETE from games_regseason
where (substring(game_id,4,4)="1985" AND substring(game_id,4,8)>="19851008");
DELETE from games_regseason
where (substring(game_id,4,4)="1986" AND substring(game_id,4,8)>="19861007");
DELETE from games_regseason
where (substring(game_id,4,4)="1987" AND substring(game_id,4,8)>="19871006");
DELETE from games_regseason
where (substring(game_id,4,4)="1988" AND substring(game_id,4,8)>="19881004");
DELETE from games_regseason
where (substring(game_id,4,4)="1989" AND substring(game_id,4,8)>="19891003");
DELETE from games_regseason
where (substring(game_id,4,4)="1990" AND substring(game_id,4,8)>="19901005");
DELETE from games_regseason
where (substring(game_id,4,4)="1991" AND substring(game_id,4,8)>="19911008");
DELETE from games_regseason
where (substring(game_id,4,4)="1992" AND substring(game_id,4,8)>="19921006");
DELETE from games_regseason
where (substring(game_id,4,4)="1993" AND substring(game_id,4,8)>="19931005");
DELETE from games_regseason
where (substring(game_id,4,4)="1994" AND substring(game_id,4,8)>="19940810");
DELETE from games_regseason
where (substring(game_id,4,4)="1995" AND substring(game_id,4,8)>="19951003");
DELETE from games_regseason
where (substring(game_id,4,4)="1996" AND substring(game_id,4,8)>="19961001");
DELETE from games_regseason
where (substring(game_id,4,4)="1997" AND substring(game_id,4,8)>="19970930");
DELETE from games_regseason
where (substring(game_id,4,4)="1998" AND substring(game_id,4,8)>="19980929");
DELETE from games_regseason
where (substring(game_id,4,4)="1999" AND substring(game_id,4,8)>="19991006");
DELETE from games_regseason
where (substring(game_id,4,4)="2000" AND substring(game_id,4,8)>="20001003");
DELETE from games_regseason
where (substring(game_id,4,4)="2001" AND substring(game_id,4,8)>="20011009");
DELETE from games_regseason
where (substring(game_id,4,4)="2002" AND substring(game_id,4,8)>="20021002");
DELETE from games_regseason
where (substring(game_id,4,4)="2003" AND substring(game_id,4,8)>="20030930");
DELETE from games_regseason
where (substring(game_id,4,4)="2004" AND substring(game_id,4,8)>="20041005");
DELETE from games_regseason
where (substring(game_id,4,4)="2005" AND substring(game_id,4,8)>="20051004");
DELETE from games_regseason
where (substring(game_id,4,4)="2006" AND substring(game_id,4,8)>="20061003");
DELETE from games_regseason
where (substring(game_id,4,4)="2007" AND substring(game_id,4,8)>="20071002");
DELETE from games_regseason
where (substring(game_id,4,4)="2008" AND substring(game_id,4,8)>="20081001");
DELETE from games_regseason
where (substring(game_id,4,4)="2009" AND substring(game_id,4,8)>="20091007");
DELETE from games_regseason
where (substring(game_id,4,4)="2010" AND substring(game_id,4,8)>="20101005");
DELETE from games_regseason
where (substring(game_id,4,4)="2011" AND substring(game_id,4,8)>="20110930");
DELETE from games_regseason
where (substring(game_id,4,4)="2012" AND substring(game_id,4,8)>="20121005");
DELETE from events_regseason
where (substring(game_id,4,4)="1974" AND substring(game_id,4,8)>="19741003");
DELETE from events_regseason
where (substring(game_id,4,4)="1975" AND substring(game_id,4,8)>="19751001");
DELETE from events_regseason
where (substring(game_id,4,4)="1976" AND substring(game_id,4,8)>="19761005");
DELETE from events_regseason
where (substring(game_id,4,4)="1977" AND substring(game_id,4,8)>="19771004");
DELETE from events_regseason
where (substring(game_id,4,4)="1978" AND substring(game_id,4,8)>="19781003");
DELETE from events_regseason
where (substring(game_id,4,4)="1979" AND substring(game_id,4,8)>="19791002");
DELETE from events_regseason
where (substring(game_id,4,4)="1980" AND substring(game_id,4,8)>="19801006");
DELETE from events_regseason
where (substring(game_id,4,4)="1981" AND substring(game_id,4,8)>="19811005");
DELETE from events_regseason
where (substring(game_id,4,4)="1982" AND substring(game_id,4,8)>="19821005");
DELETE from events_regseason
where (substring(game_id,4,4)="1983" AND substring(game_id,4,8)>="19831004");
DELETE from events_regseason
where (substring(game_id,4,4)="1984" AND substring(game_id,4,8)>="19841002");
DELETE from events_regseason
where (substring(game_id,4,4)="1985" AND substring(game_id,4,8)>="19851008");
DELETE from events_regseason
where (substring(game_id,4,4)="1986" AND substring(game_id,4,8)>="19861007");
DELETE from events_regseason
where (substring(game_id,4,4)="1987" AND substring(game_id,4,8)>="19871006");
DELETE from events_regseason
where (substring(game_id,4,4)="1988" AND substring(game_id,4,8)>="19881004");
DELETE from events_regseason
where (substring(game_id,4,4)="1989" AND substring(game_id,4,8)>="19891003");
DELETE from events_regseason
where (substring(game_id,4,4)="1990" AND substring(game_id,4,8)>="19901005");
DELETE from events_regseason
where (substring(game_id,4,4)="1991" AND substring(game_id,4,8)>="19911008");
DELETE from events_regseason
where (substring(game_id,4,4)="1992" AND substring(game_id,4,8)>="19921006");
DELETE from events_regseason
where (substring(game_id,4,4)="1993" AND substring(game_id,4,8)>="19931005");
DELETE from events_regseason
where (substring(game_id,4,4)="1994" AND substring(game_id,4,8)>="19940810");
DELETE from events_regseason
where (substring(game_id,4,4)="1995" AND substring(game_id,4,8)>="19951003");
DELETE from events_regseason
where (substring(game_id,4,4)="1996" AND substring(game_id,4,8)>="19961001");
DELETE from events_regseason
where (substring(game_id,4,4)="1997" AND substring(game_id,4,8)>="19970930");
DELETE from events_regseason
where (substring(game_id,4,4)="1998" AND substring(game_id,4,8)>="19980929");
DELETE from events_regseason
where (substring(game_id,4,4)="1999" AND substring(game_id,4,8)>="19991006");
DELETE from events_regseason
where (substring(game_id,4,4)="2000" AND substring(game_id,4,8)>="20001003");
DELETE from events_regseason
where (substring(game_id,4,4)="2001" AND substring(game_id,4,8)>="20011009");
DELETE from events_regseason
where (substring(game_id,4,4)="2002" AND substring(game_id,4,8)>="20021002");
DELETE from events_regseason
where (substring(game_id,4,4)="2003" AND substring(game_id,4,8)>="20030930");
DELETE from events_regseason
where (substring(game_id,4,4)="2004" AND substring(game_id,4,8)>="20041005");
DELETE from events_regseason
where (substring(game_id,4,4)="2005" AND substring(game_id,4,8)>="20051004");
DELETE from events_regseason
where (substring(game_id,4,4)="2006" AND substring(game_id,4,8)>="20061003");
DELETE from events_regseason
where (substring(game_id,4,4)="2007" AND substring(game_id,4,8)>="20071002");
DELETE from events_regseason
where (substring(game_id,4,4)="2008" AND substring(game_id,4,8)>="20081001");
DELETE from events_regseason
where (substring(game_id,4,4)="2009" AND substring(game_id,4,8)>="20091007");
DELETE from events_regseason
where (substring(game_id,4,4)="2010" AND substring(game_id,4,8)>="20101005");
DELETE from events_regseason
where (substring(game_id,4,4)="2011" AND substring(game_id,4,8)>="20110930");
DELETE from events_regseason
where (substring(game_id,4,4)="2012" AND substring(game_id,4,8)>="20121005");
It's nice to have the option of which table to use depending on if you're interested in playoffs or not; also makes it easy to see the effects of including playoff games by running the same query on each.