Repairing guitars in the type of condition you're describing is often rather expensive, similar to if you just want to customize a guitar, the parts can get quite up there in price. The good thing though is in both departments there is often a middle ground. That is you can repair it enough for it to function then top it off later. Given that it's a classic & they don't make them anymore that's what I would recommend. I'm of the mindset that you never give up classic instruments regardless of their state.
I have a red Mann double neck that looks like the one Jimi Page used when playing "Stairway To Heaven", I bought it from a friend of my bro's father. It says made in Japan on the back & I think it's from the 1970's/1980's. The wiring is a bit shot, the tuning pegs are 75% to stiff, the bridge screws for setting intonation are mixed & matched so it's slightly off, the nuts need replacing, & I'll have to take it in to see what condition the pick ups are in. Overall it's guaranteed to be an expensive fix but it is playable & I do play it. One day it'll be prime again, that's my goal