The real "mine" is to be seen at the Brooklands Museum, Weybridge, Surrey, together with a Grand Slam and a Tallboy - all invented by Barnes Wallis on his "home ground" of Vickers. If you are lucky you might even see "Spud" Boorer, BW's assistant in all the above. He joined Vickers in 1932 I think I am correct in saying. Nice guy, with the biggest hands I have ever seen.
Developing into a brilliant museum too.