Guys, I just beat it. I picked up an M13 a while ago which was dirty as hell for $70, but he claimed it was working. So I got it, and lo and behold, the mouse doesn't work (because they're terrible and always break). Sent him a message saying I've got to send it in to Unicomp for a refurb, and asked if he would partially refund my monies. That absolute legend refunded me the whole purchase including shipping.
That's right. I got an M13 for no money.