From http://www.its.os.org:
When we turned off the last ITS machines at MIT (the AI and MC
KS10s), we made their final full dumps available for download via
FTP for a couple of years. We turned that service off when someone
pointed out to us that in addition to keeping some important
history available, we were also making a lot of people's personal
projects and private mail files available!
Recently, the availability of several emulators for the PDP-10 has
lead to a revival of interest in ITS. Thus, we have prepared subsets
of those final file systems that we believe are free of all private
information. (We also removed anything we thought still had a chance
of being an intellectual property issue.)
Maybe there's something for you inside their archives.
--
Emílio C. Lopes
Munich, Germany