Don, have you tried the PDP-11 emulators and running Unix V7 on them? If you want to spend some hours having fun of this sort, check out: http://www.tiac.net/users/mps/retro/
Note that you can get a free Unix V7 source licence 'for educational purposes'... 😊
I have to say that I've been a lover of Unix History and I signed up for the 'educational license' you speak of the first minute I heard of it. I think it's cool to be able to look at code that is vintage in the way that V7 and things like that are. I'd like to find others of this same era as well.