Cut centers are the way that many have gone to work around this problem and it's been done for many years like this.
Hot rodders were making cut center rims on early Fjords so they could run stock caps and different tires.
It's about the only option that I know of if you can't get your tires mounted.
I have split rims and have no problem with getting them mounted at a truck tire place. If you go to a modern car tire shop, they shy away from them because they are not equipped to handle them properly.
You can also buy radial tubes to use with those stock rims so you can have the radial tire ride and handling on your original stock rims if you like.
