Depends on the shop here.
Two shops I know of are $30 drill, $15 grips and slug. The shop I go to is a bit more expensive, but the price jump is worth it - $60 for the whole package. Luckily, he's gotten to know me lately, and charges me his in-shop drilling cost ($45). Unfortunately, he's not really worth going to if you want to buy the ball in-shop, as his ball prices do not include drilling. Add in his $45 drilling fee, and you're looking at $250+ a ball.
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"For the money, for the glory, for the fun. Mostly for the money."
-Smokey and the Bandit