Set of Two Georgian Period Antique Chairs

I was told that these two oak chairs were taken out of a plantation in Mississippi. Believed to be of the Georgian Period, circa 1720-1760, manufactured by Commonweath of Pennsylvania-both of the front chair legs are on wooden casters. Photo displays the stamp on the bottom of one of the chairs is numbered 5535. The second chair bares the same stamp but number is not visible. Seatcover inset is red leather and is presumed to be original.