The "average" rate ranges from $30-$50 during normal business hours for most locksmiths. If travel is involved then there is mileage on top of that. Even factoring in replacement cost of the lock it shouldn't be $250. Sounds like a scam to me.
Anyways, I charge $35 for a "lockout" Replacing the lock would be extra of course, and my rates don't change for difficulty unless it's a safe or something similar, then it's $45/hr.
If it's exactly like the lock in the picture, you can still drill it. You'll need a fairly small bit and a piece of wire and screw driver. Drill a small hole just "above" where the pins are(Note: Not in the keyway itself). Drill as straight as you possible can. You'll feel the drill "jump" each time it hits a chamber. Stop when you've drilled 5. Insert screwdriver and turn. If it won't turn, get your piece of wire and stick it into the hole you've drilled, and remove any debris and push the top pins up. Turn screwdriver to open.
You'll most likely be obligated to buy a lock from them, but it'll be cheaper than paying the overprice locksmith, who probably is giving the person who owns the storage rate a cut anyways.
That really ticks me off.
Good luck.
I forgot to say before. *duh*