I got them from www.embedit.de and they're cheap (around 2 euros a piece, best order at least 10 while you're at it...). Go to "online shop" first, you won't find them on the first page. The delivery was really slow (like one month - I think it was the holiday season), but otherwise I have no complaints.
If you have problems ordering there or can't find anything else to order (I think the minimum delivery cost is 14,50€), I could probably sell you one or two. Should travel fine in a letter for a couple of euros of postage.