AB, Since this thread seems to be mentioning nearly all the airfields around London, perhaps you'd like to consider Wycombe Air Park (aka Booker), which I seem to remember you came to on your QXC.
There are two clubs there:
Wycombe Air Centre who I fly with, and the oposition,
British Airways Flying Club (who have a Chipmunk on their fleet ).
I expect that it may be a bit far away for you, but if you decide to come over and have a look drop me a PM, and if I'm free I can show you around.
Brooklands