based on "Raspberry Pi Zero Case by adafruit" I have make this upgrade for a 5MP Raspi-Cam.
I used this camera module:
You need four M2 screws to mount the Raspi-Nano and two M3x8 screws to put the cover on the case.
In addition, I have a recess for two M3 nuts on which you can screw a bracket
Update 2019-07-13: I added a simple Mount system to screw the camera on a extrusion
If you like my work, please buy me a coffee ^^