Ron,
These are the pictures of the 2 caramel corn kettles I saved, and the picture of the one with the burner jets in. I thought the burner I saved had more jets, but it doesn’t. The one kettle the jets must have be removed to replace on another, that didn’t work. I might have one of those other jet burners stored in cabinets in my shed, but there are too many things right now to move, to get to the cabinets. On the one kettle it did have a regulator knob that could be adjusted, by turning a knob, but on the kettle with the jet burners, there is just a place to adjust the heat with a lever. If you look at LionsDeal, you can see what the different kinds of jet burners they have for sale.
http://www.lionsdeal.com/te-226800p.html and just for the jets for the burners
http://www.lionsdeal.com/fmp-156-1006.html LionsDeal has all kinds of jet burners if you are interested in looking at their website.
Sorry my tool and whatnot shed is so messy, I need to houseclean it since weather is getting better in our area.

I did take the one kettle with the jet burner outside, so it could be seen better.
I don’t know if this will help you are not, in your search for jet burners. Our jet burners could be changed with different orifices to change from propane to natural gas or the other way around.
Pictures below
Norma