I designed a mount that uses the fourth/unused bolt hole on the Prusa MK4 X-carriage to mount a camera using Sneaks' articulating mount system:
https://www.printables.com/model/3407-articulating-raspberry-pi-camera-mount-for-prusa-m
I also included a generic step template if you want to add your own mount/arm/whatever.
No supports needed. Recommend PETG with three perimeters and 25% infill.
You might also check out the mount I made for the other side (fan doesn't block the hotend): https://www.printables.com/model/586668-prusa-mk4-timelapse-or-generic-rising-camera-mount
The author marked this model as their own original creation.