After going through a very large collection of Harrah's cards and taking out what I needed for my collection I decided to do one last merge and sort of all my Harrah's doubles. Then I updated my website to show all the available prefixes for each issue Harrah's card as well as some of the similar Total Rewards cards used at Harvey's, Rio and Showboat. If you have any interest in Harrah's player number prefixes you might want to take a look. It's a pretty extensive listing now! It also shows all the various special issue Harrah's cards I have too if you're looking for anything specific. Unfortunately I do not have any of the NFL team cards before anyone asks. I'm looking for them too.
Here's a link to the webpage where all the Harrah's cards are listed.