There is a Silver Strike Casino currently in business in Silver Springs, Nevada. However, the term "silver strike casino coin" is more likely to refer to a type of prize that was issued by many different casinos.
Silver strike coins were a promotional novelty issued by some casinos. They usually have the casino's logo engraved in some amount of silver on the coin. They most often came out of slot machines in the days when the machines dispensed coins (instead of the modern system of paper redemption tickets), so most casinos no longer offer them and they are sought after as collector's items.