Edteach. First off, love the handle. perhaps we should call you Black Beard.
Cool little pistol. I would actually go to an antique dealer to try and get a value on that piece. Being black powder, it is not classed as a firearm (federal law, state laws may vary), so an antique shop may be the way to go when looking for information and pricing. At the very least they may be able to tell you if it is a modern kit, or if it's older.