Hello John,
From the looks of the action fences, no stalking safeties and rebounding locks, it screams late 1870's into 1880's, , "if" there are any readable Henry's Patent barrel numbers those can narrow the dates considerably.
Cogswell & Harrison do have most of their records, so if they are out from under COVID restrictions they might look up the serial number and give you the details. As well, it is quite possible that Cogswell & Harrison sourced this one from Alexander Henry as it has the previously noted "look" to the locks and action. Maybe a vintage restock?
Nice old rifle, looking forward to you getting your laptop "festival" sorted and some better pictures.
- Mike

LATER: Well I'll be dipped in…..excrement……my 1,000th post