I get small pieces from the scarp pile at the local countertop shop. Find one in your area an ask them if you can get a few pieces from their pieces that are too small to be useful as full countertops.
how much are you looking for? a buddy might have some small pieces. i'll see if he has any or not and let you know.
I have gotten some from a countertop dealer/installer in my area by dumpster diving (with their permission), but good luck finding any black scraps. Mostly solid white or off white is the norm for big scraps. As a side note, I found it way too brittle for a knife scale. Had just finished one when I dropped it on cement. Shattered in about a hundred pieces.