Many places sell offset gear door hinges:
Don at Planes Plus
http://www.planesplus.com
Darryl at Usher Enterprises
http://acsip.com/%7Edgu/mod1.html
BVM at
http://www.bvmjets.com
and many others
Ed and Kevin at Great Northern Models sell TRIM Aircraft wheels and brakes
http://www.greatnorthernmodels.com
All these guys offer great products and fast service.