I have a few of these as well. I can't remember where I purchased them or the amount paid. Most likely they came from a dealer. They are very nice and I haven't seen one come up on EBAY ever (except yours). I was very active up until 2004-5 on ebay and collecting, but it became too much to deal with and I am now just starting to dig through my collection.
I am sure there are more out there, but I would insure them for 100-200 dollars each. (that amount may be way off!)