I got the same set a couple of months ago Mike. I've subsequently picked up an orange "CC" chip. Noticed the Pettibone attribution too after I got the set. Reason I purchased these as Reno can be found on this page from Larry Hollibaugh's web site. http://www.renocasinochips.com/_browze_r.php?cas=104&cit=22&st=1 Listed there with TCR#'s. These numbers may be assigned since TCR 10th edition, Larry never answered back when I asked and I haven't done anymore on the chips since. Perhaps you can try him or the KMW fellers. Thanks for the question, Gene's reply was pretty interesting.

Here is the joint pictured at the left side, on the corner by the Mercury. Looks to be about 1953.