I found this one on Tower Hobbies. Operates at both 4.8 and 6 volt packs.
http://www3.towerhobbies.com/cgi-bin...&I=LXPB42&P=ML
Hobbico CS-63 Servo Lo Profile Retract BB U
INCLUDES: One Low Profile Retract Servo
One Servo Accessory Bag (horns, grommets, screws, bushings)
SPECS: Torque @ 4.8V: 92 oz-in (6.69 kg-cm)
Torque @ 6V: 114 oz-in (8.29 kg-cm)
Weight: 1.23oz 35g
Speed: .5 sec @ 60°
Length: 1.73"
Width: .9"
Height: 1.0"