The float is brass and is in the shape of a small hockey puck. I have not seen another one even close to the same size or shape.
It does leak and I had unsuccessfully tried to solder it years back. I was able to piggyback a piece of cork onto it, which was working up until it calved in the middle of a parade last summer. Hence the search for a better solution.
I will try epoxy and some new cork, if I can't find what I need.
By the way...I just missed a complete TTX 21 carb. on e-bay, and not far from me.