Thanks very much Gregg I will follow your suggestions.
I have read where Vincent was one of the official flagmakers for the Confederate gov't. Obviously the Confederacy had standards for producing their flags. Do you know if flags produced by Hugh Vincent would have had identification marks or characteristics that could have distinguish them from those manufactured by other official flagmakers such as Henry Vaughan of Mobile, Al?
As a prominent ship chandler in Charleston, Hugh Vincent may have supplied a majority of flags for sea vessel in that area. He may have been involved directly in shipping himself owning several vessels. According to the US Coast Coast Guard, Vincent sold a schooner-cutter "William Aiken" to the US Revenue Service in 1855 for $4500. The Aiken was the first federal boat seized by the seceding states.
It seems that more examples of Vincents works would be around today, considering the demand before and during the war for his flags by major shipping merchants, the Confederate gov't, military regiments/units like the Citadel, Palmetto Guards and others along with local individuals and businesses that were struck with secession fever in 1860.