I found the original flyer for these: Limited Edition New Frontier Casino Commemorative Coin Sets. Only 1000 sets available. Each coin may be purchased for only $10 in Rewards Club Comps earned after Sept 1 (don't know what year, but guessing it was 2003 or 2004 or last ComDex) Purchase the Full Set and you'll also receive a beautiful blue velvet collection case.

I asked to purchase a set but they would only let you purchase it using comp dollars, but $10 comp dollars was about $1000 coin in. I ended up buying a set on ebay about a year and a half ago.
Hope this helps.