Most states do not require a license unless you are reselling it, which is when it would need a serial and license. And besides, the post office would see a solid piece of material in a box that looks like a car part so I wouldnt stress that either.
For myself, I want a set of action figures created. Do you plan on picking up the other colors so they can be made in more detail than 2 tone?
http://3dprinterstuff.com/page/4for each color, he has to buy a new reel of filament. which are pricey. if it is a pretty big order, it can be done i would imagine, but you would have to wait for the filament to get to his printer.
he also only has one printer head, which means only one color coming out at a time.