I think there's enough on this rifle to comfortably place it in the southern Appalachians. Where exactly? Could be anywhere from Botetourt County anywhere down as far southwest Tennessee or perhaps even on the North Carolina side of the line. But my guess would still go with SW Virginia, or East Tennessee.
Although I think it is from Virginia or Tennessee, I will throw this out there - Myron's hardware that he copied from the gun, and Ron Borron's drawing of the rifle, referred to it as Rowan County North Carolina. Myron told me that the attribution was due in part to the unusual arrangement for the front trigger guard screw and triggerplate. The triggerplate extends up beneath the forward finial of the guard just a tad, and the front guard screw passes up through the triggerplate and anchors into the wood above. Myron said he had seen this arrangment on several other Rowan County guns. I am not familiar enough with Rowan County rifles to know more about this feature. The sideplate shape is consistent with some North Carolina pieces as well, but also found in Virginia and Tennessee. Also, one more thing you can see in the photos that was sort of altered a bit in the line drawing is the slightly down-turned (actually undercut would be a better way to describe it) droop to the rear finials of the lock and sideplate panels, which also is sometimes found on Deep River and nearby NC guns. So I would not rule out the North carolina possibility, but I think Virgnia or Tennessee more likely.
This rifle has strong similarities to several iron mounted guns Wallace has featured in his Muzzle Blasts articles - some with stepped wrists , others without - and I feel ties with that group of rifles. I feel it is a great example of a relatively early "mountain rifle" made in the era when the gunsmithing families were still developing their styles and still emulating the hardware styles being made farther east and north, and being brought into the region. If I had to guess, I would put it somewhere in the 1800-1810 era, maybe give or take a few years on either end. That places it in rare company.
Congratulations Dennis - you got a great one!
Guy