Lin,
Had a closer look at your pix (you need to post sharper ones). The boxlock rifled choke gun uses normal rifling, rather than the original ratchet rifling that Col. Fosbery designed and Holland made after they bought his patent. It is Birmingham proofed following the 1904 Rules of Proof so dates to after then. Can't see what the length of chamber might have been. Believe, subject to correction, that most choke-rifled guns of that period had moved to 2-3/4" chambers, but you need to double check.
Looks like a pretty ordinary specimen. Can't imagine it's worth more than a few thousand dollars.
Regards, Tim
