If it were mine, I'd measure the width of the rearend, and start looking for cheap carbureted, RWD donor cars that run and drive. Buy the first cheap 4 door car that drives good and has the right rearend. Use the engine, trans, and rear (since they all came out of the same car, you know they work and will work together)and anything else you can. That can include the driveshaft, u joints, light bulbs, partial wiring harness, fuse block, steering column.....etc. All those little things that eat your budget before you know what happened.
It could be whatever your brand preference is, I happen to be a chevy fan, which is mostly because of performance versus price
My example, a 1956 chevy 4 door wagon (roller) for $500, a 1977 chevy Monte Carlo ( that I drove home) for $500, I used what I could out of the monte, and sold the rest for $200.
My end result was a running driving 1956 chevy that I had less than $2000 into.