Oh dear, I didn't mean to make you think I wasn't responding.
1) I had already looked at
http://repairfaq.cis.upenn.edu/sam/micfaq.htm and it didn't contain any more information about testing magnetrons than I had already completed. According to those tests (continuity between the filament pins and open circuit from filament pins to case), I have a good magnetron [but I still have no heat].
2) This cannot be a door interlock problem because I do get 3KVDC at the magnetron. Had this been an interlock problem, there would be no high voltage. Also as legg wrote, there is no way that there would be a door switch interrupting the 3KV.
I appreciate that you have parts available, but you're a million miles away (OK, a few thousand), and across the border from the US. By the time shipping was taken care of, "Cheap" would become "EXPENSIVE," and the cost really isn't the big thing here - I need to get this back on the wall (and working) sooner rather than later. I really do appreciate it, though - I have been lamenting the fact that there are no longer appliance "graveyards" anymore - just like car junk yards, there's no place of which I am aware to scrounge.
I believe that at this point, I'll just shop (more locally) for a magnetron and see how it goes. I will report back here when I know more.
Thanks folks.