Quoted from novaguy:
Correct me if I'm wrong but you could change your bracket to the one that takes the regular bell clapper that has the shell underneath.I have an extra bracket but I'm in Ontario.
Thanks for the suggestion. That would be my Plan B if I can't find the correct stepper to steal parts from.
I actually have that style stepper in my parts bin you're talking about with the bell mounted on the bottom. I'd have to bore a hole in the bottom of the stepper to mount the bell. Then, I would have to cut a 4" X 1/4" slot in the bottom for the clapper arm. Then, drill the rivets in the clapper itself so the clapper arm can slide through the new slot. Then, reattach the clapper with hardware.
Hopefully, I can find the correct stepper. If not, I'll go to plan B.