How about a large framed revolver in 22 cal? Ten shot? Offer a 4" & 6" barrel.
Convertible in 22 shorts/longs/long rifle with a extra cylinder in 22 wmr?
They already have a 10 shot K frame that will do short, long, and long rifle.
You can get an extra 6 shot cylinder and ream it for wmr. The rims on wmr are too big to work in the 10 shot cyl.