I've never seen a single with a LH lock, so I'd presume the image is reversed.
Beyond that, it looks to be an aged amalgamation of parts, with what might be a period ear trumpet (aka: pre-historic hearing aid) added to the front, made to resemble a Blunderbuss - and IMHO not worth more than a decorative value.
The more I look at this the more I am thinking this post was a gag since that thing is so obviously just a conglomeration of junk and nothing more. I don't think anyone would seriously be asking what it's worth and this is probably just somebody's (bad) idea of a joke.
I guess it just doesn't take much to entertain some people.
A forum community dedicated to Sport shooters, owners and enthusiasts. Come join the discussion about optics, hand casting bullets, hunting, gunsmithing, styles, reviews, accessories, classifieds, and more!