Where do I find a good 360 servo?

Other Hardware Motors, Mechanics, Power and CNC
1

So I need a servo that can HOLD POSITION, and move from 0-360°. Most of the continuous rotation or full rotation servos I've seen so far are just a version of a DC motor with no potentiometer and no position mesurement.

Where can I find a servo that works just like a normal servo, except that it doesn't go from -90 to 90 degrees but -180 to 180 degrees instead. Or just something that can move continuously and yet hold and measure position at the same time.

2

Have a look at sail winch servos.

3

Sail winch servos with ~1.5 turns to ~6 turns.