My search (usually done on eBay.fr & eBay.de) is:
jeton* casino* -poker* and I set the search to run worldwide.
I do the same for:
casino* plaques* .
For U.S. eBay I usually just type in jeton*
After those I usually go to the Casino section of eBay and start in with the following keywords one at a time:
German* France* French* Pearl* Oval* Spanish* Spain* Euro* Africa* , and a few others.
Of course, all this is worthless unless you are searching for jetons or plaques for the most part