I bought seven rims at a local wrecking yard for about $60 bucks apiece but had to have them sandblasted and painted (another $150 for all as I recall). The Bridgestones run around $200 apiece but you can often beat that at shops who specialize in fleet work. I think I paid about $185 each plus the usual mounting & balancing.
If you can find a Chevy c-3500/4500 dually rear end around 1998...it will come with the 19.5 rims that may well match your lug pattern (it does mine) and has a bunch of gearing options. They came with one of the very best rear ends out there (in my book)...the Dana 80HD wide track. It is a brutally tough rear axle rated to 11,000 pounds and is very close in width to most early Chevy frames. And...you get beefy disk brakes in the bargain. Oddly, my original 1946 axle had spring perches that were slightly wider than the new "wide-track". It took some very careful measuring, but the welding work was pretty straight forward to re-locate them.
Modified spring perch
New Dana 80HD axle
It involved some work, but I had no desire to run cross country at highway speeds on crappy tube-type, bias-ply tires.