Hello! First of all, good luck on your search.
Two bits of advice from having searched for and purchased a boat of similar vintage recently (although slightly smaller at 32'):
1. Seller's Pricing for early 1970s era boats seems almost totally random, there are some really overpriced pieces of junk, and really inexpensive gems out there. Don't assume a boat is better or worse because of its price (especially if you are looking to buy from the owner rather than a broker, as I was).
2. Buy below your budget and leave the extra money in the refit kitty. Owning a large boat is really more expensive than you probably think it is (certainly than I thought -- and I did try to do my homework beforehand!). This will be easier to manage if you buy lower than your max.