Bladeswitcher,
I do not know what the market value of your gun is, but it is a beautiful British boxlock with arguably the strongest possible barrel jointing method, vertically dovetailed chopper lumps. I think you have a real sleeper there.
The Brits didn't care for that method much--probably because it didn't make bottom line sense, given their hand-crafted vs machine-made gun trade. Here's Burrard's comment on the BSA dovetail system:
" . . . the cost of cutting out the dovetails to an accurate fit by hand would be altogether excessive. Where mass production is carried out, special machinery can be installed for doing this work, but it would not pay the ordinary gunmaker to set up such costly machines, as he would not turn out enough guns to get back sufficient capital on the machine . . . So, from the point of view of economic manufacture, this method is only suitable for a factory where guns are manufactured in great number."
