What color is your car right now and what was the original color? My car is signal red but was originally forest green. I would had to call it the Green Monster instead of the Red Rocket but I kind of like the later. Since your car is no longer original, and let's face it, few are, why worry about it.
I tell everyone the same thing: ' It will take longer than you expect and cost more than you want '. That's the nature of old cars.
If you want a firm price some places will make it so high it will choke you. Other places will be low and start cutting corners to meet the estimate. I work on a '' time and materials '' format. If I could see all of the problems I might encounter ahead of time, or I could see through paint or inside of engines I would be able to ball park it. I can't and I won't. I charge for the hours my guys work on your car but generally don't add very much for myself.
You should be able to get a lot done for 80K. If your car is a good driver you could go the rolling restoration route which means drive in the summer and restore in the winter. Mechanical stuff first, then paint, then interior. If you draw it out over 4 or 5 years it won't be too much per year and you can get to drive it during most of that time period to sort out mechanical problems. If you don't have a purchase price to consider you are already well if front of the curve.