Anton....
Had been checking for closest places to build time with some friends....Here are two flying clubs right at the donmuang airport VTBD in Bangkok(old Bangkok International Airport)
BAC
Bangkok Aviation Center :: ?????? ???????? ?????? ?????? ?????????????? ???????????? ??????
Cessna 172 Glasscockpit also available, diamond 42, seneca
ROYAL SKY
RoyalGroup - One Stop Service For all You Need
Cessna 172 skyhawk da40 PA turboprop
Regarding JAA validation you can email or call them and ask, as I am not updated on the process, been quite a while back since I last checked.