The best option we have is the Karrier ST205/75R15 Radial Trailer Tire - Load Range D item # AM10245. These tires are slightly smaller than your 215/75/R15 tires but will work great on your 1966 Yukon Delta camper which came stock with 14" tires originally. These tires are a load range D with a maximum capacity of 2,150 lbs at 65 psi.

Your wheels are most likely the 5 on 4-1/2" bolt pattern but the only way to verify is by measuring the hub as they could have been changed in the past 25 years if you are not the original owner. We do have the Westlake ST205/75R14 Radial Trailer Tire w/ 14" Silver Mod Wheel # 274-000053 which are a similar design to the wheel you sent. We do also have options with aluminum wheels like the Westlake ST205/75R14 Radial Tire w 14" Condor Aluminum Wheel # LH37VR. The aluminum wheels are more corrosion resistant and better if you use your boat trailer in salt water.