GO PRO Magnetic base
Ive remixed this great go pro tripod mount and added 4 holes to insert 10X3mm neo magnets. four magnets is enough to hold up my camera but i made the holes deep enough to fit 2 layers to increase the magnets power.
EDIT. The best mount ive made was printed after scaling the model up by .1% The magnets fit much better and camera fit well. I dont know if it was because my plastic shrank more or what so you may need to try and scale for best fit