Another one is the Motor Glider Club at Hinton. The CFI, Clive Stainer, is an absolute Gent and has been in the game years. His number is on the airfield website
Hinton-in-the-Hedges Airfield
Hinton is 10 minutes off Jct 10 of the M40 (of which 5 minutes is dual carriageway) and about 50 minutes drive from Uxbridge.
LJ