Here are two I bought in the 70s, fired a few times and put away. I just took them out to clean and handle.
That is a belt or sash hook on the back but I have never used it. Not much too grip and the ball triger allows only one finger to actually hold the stock. A big hole in the muzzle of the 9" smooth bored barrel!
58 caliber and I believe I used a PRB over 50 grains of fffG.