For what it's worth, the fully formed concept of a "Carolina gun" without further description being necessary for contemporaries is used in the Anglo world as early as 1738, with the exception of the lock this gun appears to fit that profile. Von Reck naively depicts something along these lines around the same time. Sadly the references to "Indian Trading guns" going to both Virginia and South Carolina in the 1705-35 time frame that I am aware of don't get into spectacular detail but there is some kind of generally accepted common type suitable for Native customer's market desires that early (Wm Byrd's papers mention "18 Indian guns 4 foot per the [illeg...barrel???]" as early as 1689, his 1684 orders for "guns" as part of an order of "Indian Goods" specify dog locks in that era). The lock on this gun, if English is what, maybe 1690-1715ish? IF the barrel mark attribution/dating for Williams is correct then I'd say the lock is likely a replacement. The early restocked gun by Sanders at the MOFT has a similar lock and may be as late as 1725, of course it has a different sideplate and etc. Devil's advocates might point out that everything on these is very retrograde, but the sideplate certainly is close to one from Frederica that is from the 1740s.