Hi, Andrew,
The 317- resistors are standard stock items in many catalogs. I may
have one here, though in case you're having a nasty time trying to
find one.
Regarding the 307- attenuators, are these the thick-film-on-ceramic
resistors that slide over two metal pegs and get a spring clip on top
to hold them in place? I think the 7A19 uses them. If so, I may
have some. I gathered up several of them with the idea of using them
to make a really hot 50 ohm switchable attenuator one day. Never got
around to it and ended up finding a pair of hp 355 attenuators
instead. Let me know and I'll look up the parts.
Dean