Where are you located? There's a chip & casino collectibles show in Las Vegas next weekend, if you can attend. Might be some items there, although Meadows Club is tougher place to get memorabilia from.

BTW, I checked the UNLV Library for items in their collection. The only items that pops up is a color postcard (link below) and a B&W photo of the same facade.

http://digital.library.unlv.edu/objects/sky/66

Good luck with your search.