Hello Victor,
There are few, if any, casinos that will sell them to you. They know it will probably cost you more than the face value to get one. I have won them for as little as 25 cents or as much as 50 dollars. Other places you can find them is from coin dealers and coin shows. I have found quite a few at shows at fair prices (as little as $12 a piece if you buy a few). One more option is to talk to club members. I think a lot of the members collect a little of both and may want to trade strikes for chips.