Reported on TCB by Larry Hollibaugh reported a find of at least 18 Harold's Club $500 chips by someone who contacted him via email. Another ebay seller also sold a few chips and claimed he bought them from the original seller. Here is the link to the post.
http://www.thechipboard.com/archives/archives.pl/bid/399/md/read/id/1262427/sbj/harolds-club-500-chip/
The chip was listed as a R8 in C&W, which also noted a total of 8 exist. TCR15 lists it as S- value code. Here is a pic of the chip from the Chip Guide:
