Tom,
Sorry you would take issue with my poor use of the word "stencil." The close similarity in cloth sewn on cloth, the cut-off fronds sticking out from the trunk, the overhanging fronds with leaves pointed downward appear to me to have been conceived and fabricated by the same hand and to my limited knowledge match no other pattern produced by the state. If I could see a news illustration in an Alabama newspaper with this pattern of tree shown as an example, one might could believe that someone saw this illustration at random in Alabama and chose to throw together a South Carolina flag just for the heck of it that just happened to be captured. But as a possible fabrication of this flag's existence I think it's kind of far out. Like I said everyone has an opinion, some farther out than others.
Thank you for the photos. I see great similarity between the cut of the trees. Looks to me like mid-1861, Charleston, S.C.