1972 Shasta Fridge Replacement

Assuming it cools when operated on LP, there's a reasonable chance it could be repaired fairly easily or inexpensively, though of course that depends on what is not working. The fault must lie in the electric element or in the wiring/control bits that lead up to it. It could be something as simple as a broken wire or a fuse blown from age.

If it needs a new element or other part, I have no idea whether they would be readily available or not.

Replacement would be as "simple" as finding something that fits and then performing the grunt work of getting the old fridge out and the new one in and tied down to the structure. Obviously, if replacing with an electric only fridge, the propane line would need to be properly plugged or removed.

If you always stay at sites with electric I suggest a electric fridge. We had a friend who's 17 year old dual power fridge died she was a full timer but just circulated between three different campgrounds as a volunteer. She picked up a 3cuft fridge from Lowe's and has been fine for the last 4 years.

Measure the refrigerator. Maybe you can find a regular electric one the same size Home depot, or anywhere they sell appliances.

Many use electric only.