Why doesn't someone just set up a production line for Spitfires, and then every time one is dug out of the ground, its data plate can be screwed in to make one of them genuine? (supposing that any variant can be configured from a basic airframe).
The whole business is a con. I'm more than happy to see fake Spitfires in the sky, but I do mind the public being expected to believe they are original WW2 aircraft.