These wheels can be dangerous but you should be able to find a tire shop in your area to work on them. Its been covered on here many a times. Also bias ply tires are still available. And some shops will even put a radial on ther for you.
For Steel Wheels You can also use steel 8 Lug Wheels from a *ord, or *odge. I would reccomend 16x5, and you will still have problems in the front with wheel clearance against the tie rod ends. So you can try wheel spacers made br Mr. Gasket, they make 8 Lug Spacers in 1/4" just make sure you have enough threads left on the studs, do a google search on these. I was about to go this route when I found someone in town to work on my wheels.
Birge
