I had a quick look around for some 3ml dropper bottle and found 2 sites selling the same thing and looks good. This will be perfect if it fit the width! It's .5" thick and I don't have a ruler to measure the PCC holes but half and inch thick sounds too big. Might have to look into a 2ml bottle.
http://www.ultralightdesigns.com/products/packing/miniBottle-3.html
http://www.thevaporpro.com/3ml-dropper-bottle.html
http://www.ultralightdesigns.com/products/packing/miniBottle-3.html
http://www.thevaporpro.com/3ml-dropper-bottle.html