Yes, such a thing does and did exist.
Spitfire RW382, flown and owned by George Haye is painted in the markings of the Mk.IXc‘Porky II’, which was assigned to the USAAF 309th Fighter Squadron, 31st Fighter Group, stationed in the Mediterranean Theatre in 1943 and flown by Lt. Robert Connor.
So it's a Mark 9 Spitfire, like MH434, flown in American markings over an airbase built for American bombers in WWII.
Little wonder then that we've asked George, a fantastic addition to the Air Display's world and all round good bloke, to close the Airshow each day in the greatest Anglo American way we can think of.