I was using the straight one from Andreas Gohr. however when i put a door on my enclosure the camera arm bumped into it. So I made a bent one that appears not to clash with anything. It does get close to the Z frame so when the bed is all the way back you lose some view.
Please check out the link to Andreas Gohr's design for the full arm with the camera case and post needed.
https://www.prusaprinters.org/prints/7064-customizable-raspberry-pi-camera-bed-mount-prusa-m
The author remixed this model.