I don't know if they will work with your application, but I am using "k" type thermocouples in my pots. I got the bulkhead fittings from williams home brew supply. Here is the link: http://www.williamsbrewing.com/WELD-..._P1032C141.cfm
The only problem that I had with these is that my thermocouples are 3/16", and they did not fit in these fittings, I had to drill them out just a hair, and they work perfect, no leaks, thermocouple precision!
You can chek out my videos to see my setup if you like. Hope I helped.