David, if it's a Holiday Rambler, it would likely have the Dexter (DexStar) wheels that are 4-bolt and look like
THIS.They made them in several widths in 13,14 and 15" diameters.
There are no automotive or other bolt-on alternatives for these.
You might be able to pick up spares at an RV dealer but they are pricey.
The best bet is to just pull the wheels and carry them to the tire store.
Also, rather than taking a chance, you should pull the drums, check the brakes and repack the bearings before getting on the road with it.
Ricky
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