@barry
I wrote about RC-Servos
They have motor, motor driver , motor controller, position feedback and needed gearbox , all in one component
RC-Servo motors have three wire interface for controlling and power supplying.
Controlling of the servo motors is used using pulse controlling.
The control pulse is positive going pulse with length of 1 to 2 ms which is repeated about 50-60 times a second.
The controlling scheme is very easy to impelement with some electronics.
You can easily build a timer circuit using 555 timer chip for generating suitable controlling pulses
or you can use small microcontroller program to do that.
Movement 90...360 degrees , with small modification continous run.
Torque 1....40 kp/cm.... and over
Reasonable prices
Read attached links in post #4
KAK