I'm fairly certain Merrill Lindsay mentioned the Tileston rifle in print at some point. It's been known since at least the 1960s. Lindsay pointed it toward a Massachusetts maker, mentioning Tilestons being south of Boston if I remember correctly. Wallace has tried to place it in Virginia and I recall him mentioning Tilestons there as well.
Someone here may see this and may opt to post some photos. There are a lot of very good, high resolution photos of this rifle but I'm not involved in the "permission" string. I have handled it when it had recently been auctioned and was at a KRA show in the early 2000s, and it sure does seem to be a really great early rifle. It's definitely early. The iron furniture on it is probably the most accomplished iron furniture I've ever seen on an American rifle - you would think you were looking at modern investment castings, it's that good and that comparable to brass furniture of the 1770-1780 period. The lock is clearly a Brit lock of exceptional quality but I personally would question the originality to the rifle. It's definitely been on the gun a very long time but it's ever so slightly mis-fit. The pan fence is actually back behind the breech of the barrel. Given the quality of the rifle, I have a hard time seeing it as being made that way as original work. the barrel signature (stamped) and the 1773 date: one can only wonder. It certainly seems all original. Some think the piece is a restock of lock and or barrel, some think it's all original, some think this or that. It's always been a somewhat controversial piece. Some portions of the furniture have a residue on them which appear as though they were coated with some type of black preservative, which I know Wallace has mentioned in regard to southern pieces being coated. Speaking for myself, there's not enough of it to make this determination and it could be simply severely oxidized oil. I don't know.
I personally tend to take the gun, including signature and date, at face value albeit possibly with an early in-use lock replacement. It's really an awesome rifle, and it does seem architecturally and stylistically to match the 1773 date.
The carving around both sides of the comb matches almost identically one of the New England fowlers in Grindslades book, as in "same carver" identical, which lends a lot toward the long history of a New England provenance.