I would try to find some 1-piece wheels. I'm not sure on what interchanges and good used ones are a real good way to go, but I would call your local Wheel and Rim dealer and see what new ones would cost. They may even have some used ones for sale and also maybe able to tell you what would work on your truck.
I'm going to guess that you have 5-10 Budd's on that truck.
Bill
