The first appearance of wire inlay on colonial period longrifles is on Oerter’s rifles. Wire inlay is common on later New England rifles. So, wire inlay is rare on rifles in the period of interest. Plausible? Yes. I note that Oerter essentially replicated established relief carving patterns with his wire inlay. So I’d lean toward replicating carving on a known rifle. To me, a build based on the Brass Barreled Rifle would be a good candidate for use of wire inlay. It would be a creative piece.
The attribution of the Faber rifle to a particular location is still up in the air for me. If I recall there’s another gun quite related to it.