All second hand because I've never owned one, but supposedly Lyman made them years ago and early in the models. But they got nervous about 58 cal in a 15/16" barrel and lawyered up, and quit making a 58 because none of their guns were set up for 1" barrels.
From what I've heard, they're really light and handy, but I'd expect max loads to be a lot less than with a 1" barrel. I've got a couple of the 58 cal T/C Big Boars with the 1" barrel, and they're plenty light and handy. I can just imagine how much lighter a 15/16" barrel would be. Not a criticism, and it actually sounds pretty good.