Bc
Congrats on scoring a 760 in 35Rem. I have several
Your best bet for an extra magazine would be gun shows or gun smiths. Numrich and Brownells are out of stock. Maybe Amazon would produce one. Yes, a 308, 243, etc. magazine will work. My 7600 magazines work in my 760's. You might also try an ad for one right here in the classifieds.
For the rear sight I'd check gunsmiths/gunshops. They usually have boxes of old stuff they will let you look through to find what you need.
If you are looking for a peep sight, Brownell's has one that you install in the rear scope base holes.
I restored the wood on one a couple of years ago pretty much as you describe yours. Formby's furniture stripper worked for me--might have to apply it a couple of times. About four-five hand rubbed coats of Birchwood-Casey Tru-Oil following their directions.
Hope this helps.
WN
