I picked one up directly from them a few months back. It may be a little more than one on ebay, but assuming you need t for doing your testing, it may be worth the extra $ to get one from them that you know is accurate and not damaged, etc., after all, you will most likely make you decisions on development and exposure off of this. I believe you can also ask them to proof the wedge before sending to be sure the values in the wedge are accurate to the density measurements listed. The person I spoke with there was very nice and I received it a few days later.
Hope this helps,
Colin