I only found the Commemoratives at KB, WM and TRU. WM wanted $10-11, and TRU and KB were around $12-13. Online retailers were just getting started back then, so if you actually found a site that had them for sale, they were about $20 each just for them being so limited. These things disappeared fast. Only one or two cases ever showed at any store, and you had to be there right away to get them. Some employee at KB almost refused to sell me some of them because he wanted them for himself. It's any wonder they're broke.
I have a complete single carded set of both series, as well as the Battle Cat and Panthor packs which ran about $20 at WM. Never did get the TRU or JCPenney exclusives, and I regret it now, since those are the most valuable pieces in the line (read: ones I can't afford.)
If I had to part with my collection for any reason, these would be the only things I kept.