It should be no problem to just remove the little bit with tweezers, or with your fingers if it's big enough to grab. It's probably not "in" his eye, just sort of lodged in the little fold of skin between the spectacle and the neighboring scales.

Also, just to be on the safe side, you should probably post a pic of your snake poking his head out from under a blanket to watch South Park. You know, just to make sure we get enough cute snake pics today.