I had the same problem with my '91 Eldiss Typhoon. I tried everywhere to get a thermocouple for my Princess oven. I was told that as they're no longer produced spares had dried up. I tried the caravan breaker & came close a couple of time. Every one was telling us to just get a microwave but the food cooked in them doesn't taste the.
In the end Ebay had a new, different make oven for sale, cost