Hey Lin -
The best we can figure is that there are two available (Manchester and London). Both commemorate the openings of their two new casinos (June 2002 and Nov 2002 respectively).

These will be Chipcos and be No value chips available from the Hard Rock Site (www.hardrock.com) in the shop. The site mentions them being limited to 1000 peices (seems like way too small, but that MHO). I ordered a couple but haven't seen them yet. Hopefully when someone gets theirs they can post an opinion.