Hi, I remembered seeing these on Ebay yesterday.
Here's a link to someone who has thousands:

http://www.ebay.com/itm/5-CHIPS-FROM-CASINOS-NACIONGALES-DE-PANAMA-100-CHIPS-/200681576763?pt=LH_DefaultDomain_0&hash=item2eb98dd93b

And another Ebayer:
http://www.ebay.com/itm/Casino-Nacionales-De-Panama-HOLIDAY-INN-5-00-Chip-/370293158456?pt=LH_DefaultDomain_0&hash=item5637313238

If for any reason these links do not work, just type the item numbers into Ebay
-200681576763
-370293158456

Hope you find what you're looking for,

Rene Melanson