What to do with 16.5 in. wheels?

[Earl Filter]

My turd '77 has 16.5 in wheels. It currently has at least 6-year-old tires on it that are dry-rotted and just downright dangerous (I haven't even driven the truck, and it was towed to my house). This is my beater, and that's probably all it will ever be. It has 31x10.50x16.5 on back, and 9.50s on the front. Do I:

a) find some tires to fit the wheels? I've looked quite a bit, and there's almost nothing out there in 16.5. I think the 31x10.50x16.5 is what I would do all the way around if I keep these wheels

or

b)buy some late-model 8-lug wheels in 16 in.? It's be easier to find tires, and cheaper, too. I see some plain painted new ones on ebay for about $250-275 shipped.

Keep in mind I paid $300 for the entire truck, and I have another project that requires more of my money right now. I just want it to roll somewhat safely down the road.