The one I share could have been for sale if my plans to acquire something more exciting had come off but unfortunately the others didnt want to play (secretly I am glad to still have a chippy 'on the fleet').
DHSL is a good start (note article in a certain piloit magazine this month written by yours truly!).
I would suggest the better option is ARC at Duxford. John Romaine gets to work on a number of them and is often aware of machines for sale (we bought ours there)l.