I traded one of mine within the first 10 minutes of receiving them lol, and another one of them was before they even arrived. Unless you're quick and grab some during a 4grabs sale, you're only gonna get one if you REALLY want one. A lot of people only trade too and never sell.
Keep and eye out over at the Clack Factory forum's 4grabs sale. They happen quite infrequently, but do happen.