I still believe the stock is original to the rifle, but has seen a very hard life. I have seen many of them in similar condition. The local term we have for a stock in this condition is "skint". It is obvious all of the wood around the barrel tang has been replaced.
The barrel tang is not Jamestown school like the rest of the rifle, but is Davidson School. The Jamestown School largely put many of the other N.C. gunsmiths out of business in the 1840 - 1850 period. I have seen several late Henry Ledford signed rifles with this stock architecture and a Davidson school barrel tang. This rifle was likely made by one of the 19 Davidson School gunsmiths in the Jamestown school style. I have also owned and sold rifles made in Alamance, Caswell, Rockingham, and Mecklenburg Counties that copied the Jamestown School just to stay in business.
The bullet mold used is a pistol mold, but does have a cavity to make round balls. I would guess this was used after the bullet mold that came with the rifle was lost.
As to having a single brass dove-tail front site, only 70% of the Jamestown rifles I have owned or sold have double brass dove-tails on the front site. 30% of them are just like this one. If the rifle was made in Davidson County, as the barrel tang indicates, I would expect it to have a single brass dove-tail front site.
Best of luck,
Michael