In his charming way, Joe is telling you the gun is not very valuable, and he's most likely correct. My first-blush s.w.a.g. is $500-750, based on how little information we have to go on. But I think Joe's dead wrong that it was "cheaply made." It was almost certainly a decent gun when built, and still is, although it could really use some TLC and perhaps cautious restoration down the road.
If I was you, though, I wouldn't spend a dime on it until I'd spent a couple hours cleaning it with gun oil, Murphy's soap, paste wax, a toothbrush, 0000 steel wool and a soft rag. Be sure to run an oily swab down those bores a few times, too. You'll be surprised how much better it will look.
Will wait on comments from the real experts, but I see a "flashy" utility percussion scattergun built c. 1830, maybe at least partially on the Continent, for resale by a Birmingham shop in decline and soon to close its doors. It may have been intended to appeal to the colonial market (Australia, South Africa, India, etc.) ... a working-man's gun with some "bling" added to appeal to a gent who might have more money than gun-smarts, or one forced to order it sight-unseen.
You can find rows of modern-day shotguns in the racks that fit the same description and marketing philosophy ... take a well-built, mass-produced, $1200 20-gauge and add coin finish, some gold-inlaid quail and rolled engraving, or maybe a photographically enhanced stock, then double the price, and you're looking at someone's future heirloom.
My two cents. Good luck and Happy New Year to all. TT
