I think the carving is somewhat amateurish, and that's why I said the last one he made.

Shelby could be right on the enhancements.
As for the patchbox, what can be seen of the engraving, is Dickert style and is also on his other rifles, and the PB latch looks good as well. I can't see the hinge well enough to tell whether it's correct. In the pictures, the door looks a slightly different color that the side plates. I wonder if the pictures are poor purposely.
Lastly, the signature on the barrel looks good and strong, while the overall remainder of the rifle looks somewhat weak, and amateurishly made.
Without an in hand inspection, I wouldn't bet the bank on this one.
PS. On second look, I think most of the incised carved lines on the cheek piece side were cut well after original. I would think the original is the incised carving ahead of the cheek piece. And the dark colored semi double C behind the cheek piece. Most of the remainder; after the fact.
Here's a better pic. Click it for a better view.
