What do you think? Buy, or keep looking?

[Dotes15]

Ive been looking for a work/hauling truck for a while now to move my smaller trucks, friends boat, the cars my brothers blow up every few months, etc. Ive kinda been wanting a square body crew cab dually with a 6.5. I asked around at work and one of the other mechanics said he had a 77 crew cab 3/4 ton camper special 454/turbo 400 2wd truck that he traded for a few years ago and doesnt use. The good, it has 56,000 miles on it, the heads were rebuilt approx 3,000miles ago, runs good, suspension looks and feels good, tires are 50%(just flat), glass is all good, good hood, grille, lights, and bumpers. The bad, it needs rockers the whole way down on both sides(how do you do that on a crew? I cant find panels.) all 4 doors have rust holes by the rockers, needs both fenders, needs a bed(im ok with that so I can delete the camper hooks), it needs the usual stuff on the inside cleaned, seat covers or seats from a newer truck, little dash fixing and such. I can get doors, bed, and fenders for cheap around here. Ill probably fix the body and paint it black maybe add some markers and put it to work. He said he would sell it for $700, should I get it or keep looking?? Sorry the pics arent great I didnt take them.