Here’s my final result with this bell. Not the best repair but it works and it is my first one!

I tried two types of metal bonding substances.

Tech-Steel, which has both materials already in place – an inner core of one material and an outer core of the other. It seemed easier and impossible to get the proportions wrong that way. You cut off the amount you need, kneed it until uniform, then apply within 15 minutes.
– I found two things with this product:
1) kneeding it dried it out, so it did not stick at all.
2) a dried ball of this material would make an excellent replacement clapper! You could mold the hanger into it.

PC-7 was the other type I tried. It comes in a double sided tube. You remove the same amount of material from either side and mix until uniform. It stays workable for about an hour, according to the instructions. I found getting the proportions correct was much more troublesome, and it wouldn’t set for me until I left it over night.
The past form this became was easier to apply but if it wasn’t held together until it permanently hardened then it wouldn’t stick together (once apart) after 15 minutes or so. If you left it over night then it held.