This prints in about 15 minutes. One ring, one back.
Put the safety pin through the back first. Cut out picture from magazine, place between the ring and the back. snap together. Yaay. Now you have a cool pin.
Note that the ring has a 'front' side that is slightly wider than the back.
for waterproof pins.... put a piece of saran wrap over your picture.
You'll need a well tuned printer. The circles need to be circles, and any stringing will inhibit the ability for the two pieces to snap together tight.
Sample shown is printed at 150% x, y; 120% z. Should be able to scale to most any size you need ... providing your safety pins are big enough for the slot on the back.
Print settings nothing special. This is printed at .2mm height