OK just purchased DH and DS at the bowling alley they bowl at. If you purchase it on site at a alley they drill for free usually.
If you purchase one at DIcks or outisde the alley they gave me a price of 50 dollars for straight drill no curve set in.
Check out the lanes near you and price around. You can often get balls that were ordered and no one had drilled for less money.
DS's was 100 and DH's was 90 got a clearance one that has a crazy spider in it. That including the drill at no charge for them.
Good Luck!