2004-05 Topps Chrome Basketball Forum

Per the glossary entry for this set, the 6 group C cards:

http://www.tradingcarddb.com/Notes.cfm/sid/29198/2004-05-Topps-Chrome---Chrome-Town-Heroes?Note=C

were all SN above 1000, so they should be relatively common in a 30-card set where most of the cards are SN500 or less, but I cannot find any of them pictured online; Beckett, COMC, Collectors.com, eBay, Google are all blank.

Anybody know the story on these?