Flame Safety Device Replacement - 1975 Tradewind

[505live]

I have the typical "fridge won't stay lit" problem with the dometic in my 1975 Tradewind. It has the thermoelectric flame safety device. I checked/cleaned the gas valve end, I still need to get in there and clean off the sense end.
It would be nice just to replace it though after all these years but I'm having no luck finding a part, is this thing a unicorn now? Also if I want to test for the 20 mV output where do I probe it? Finally, anybody know of a way to update this to a modern thermocouple?
Cheers,
Nate

[505live]

I think I was just over complicating my search by including "dometic". Standard water heater TC should do the trick I think.
https://www.amazon.com/dp/B00076VESY..._U34RCbDEFY3H5