Steve, you really don't want to risk life and limb on split rims. They are extremely hazardous. My advice is to take your split rim to a local tire dealer and get a quote on a safe repacement. Be sure they quote you on a trailer wheel with 2600# load capacity. If you know the bolt hole pattern and the offset, you won't need to take your old wheel in. I've bought new trailer wheels for $26 each.
There is a very good reason why most tire dealers won't work on split rims, so if you have to scrap the tires along with the split rims, it's the wise thing to do.
May you camp where wind won’t hit you, where snakes won’t bite and bears won’t git you.