Looking for a Thompson Side lock for a project. I want to make a short handy Muzzle-loader (approx 12-14"barrel).

Something that was neglected works great for a proof of concept.

My dream gun would be a .45 White Mountain Carbine. Cut it down 1: in front of the round barrel portion. Large bore makes up for short length - more volume to burn powder charge.

Looking to say extremely reasonable (price wise) as this concept may not "pan out".