Be aware these large servos need many amps, perhaps 4 to 8A.
What is the application? is a servo the best solution? Would a linear actuator be better?
What positioning accuracy do you need (servos are usually not great).
basically I need to move an heavy object of + - 10° from the center position
"Heavy" is not a number, and details matter for mechanics calculation. Have you calculated
or measured the actual torque needed? Guesswork can be expensive, best to be sure.