I am having a hard time locating an entire set but I did find one single 2" Diameter Perfect Condition Elephant Ivory Billiard Ball priced at $169.00. So I'm sure you could guess from there.
A billiard ball is a small, hard ball used in cue sports, such as carom billiards, pool, and snooker. The number, type, diameter, color, and pattern of the balls differ depending upon the specific game being played. Various particular ball properties such as hardness, friction coefficient and resilience are very important to the finer points of gameplay.]clarification needed[