Here I decided to take advantage of the shrinking properties of shrinky dinks to try and make small things. The shrunken gears here are about 0.25inches in diameter. The gears (and enclosure) were cut at 2.3x their final size and carefully heated in the oven. The gears were a bit testy and needed to be flatten a bit post-bake but turned out well in the end.
This is partially functioning device. Tweaks need to be made to the process to ensure better seals and geometries between the gears and the pumps
Note: Lasercutting settings for the X2 600 in the shop that I used are 25% power, 35% speed, 300 PPI though you should probably check with John before cutting polystyrene.