Weld is relative. I do use weld bungs from various sources. The sender thread is 1/8" NPT so you are looking for a flanged bung in that thread. I buy them in bulk so I'm not sure of a value for a single. But, if you like, I can send one out for postage and the price on the website which is what I paid.
http://www.bungking.com/stepped-npt-bungs/
Or if you have a spare pan and want me to silver braze it in, I can do that. Costs 20 bucks plus shipping and that includes the bung. (provided the pan is clean) I charge 148 dollars to clean it.
