74 Hang Ten

I have an mostly original, running, driving, numbers matching, Hang 10. Mostly body work to repair some rust spots. front seats need redone but I think that the center cloth strips are salvageable. What kind of money are we talking? I just got it and need to replace center 8 3/4 rear pumpkin, originally a 7 1/4 rear. Still has the original 318 and 904. Thanks, Alan