Without handling the gun I can't begin to definitely determine the age or area of origin.Of one thing I am sure ,this is no trade gun.I understand that Wes White had documentation that after the revolution one of the largest groups of customers for Lancaster guns was Indian market hunters. At the earliest{educated guess}I would place this gun around 1800 +/= some 10 years.It could even be a recent cobbled up and aged gun or it could be a "classic"homemade barn gun.By this time Leman, the Henrys, and others were turning out quality trade rifles for Indians and Whites alike.
It has become very typical for those wishing to sell guns that don't fit any regular mold to label them as "Indian trade guns" usually with tacks and/or rawhide wrapping thus cashing in on a certain mystique. After all "everyone" knows that a "genuwine Indan trade gun" is highly desirable .I would not have been surprised to see tacks and rawhide wrist repair on this gun.Granted, this type of decoration would be likely found on Western guns but add ons aren't limited to the West.
I guess then that I would make a wild stab in the dark and hazard a guess that it is cobbled up and possibly home made gun. Old/new ? don't know but CAVEAT EMPTOR here. I think that unless this gun has some hidden assets or a fabulous and documented provenance that $2,450.00 is bit more than I would care to spend.I would have to have a real come to Jesus meeting with myself before I paid any where close to that much.