For futaba, I'd look for servos along these specs
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXRJS5
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LH7438
Now, these look good on paper, but I'd look over some reviews as well before buying.
I'm used to other companies' terminology on high torque/high speed so didn't expect these to be labeled for torque but the specs look good for a tc.