They are taking you for a ride. I suggest you call them right away. Ask them if your regs are done, or if they have started. If they say no, then take your reg elsewhere.
I would insist that they change all the o-rings. Any serious tech will change every O-ring when they open a reg. The reason is that O-rings cost the shop a few cents, and if you bother to take the O-ring out and dress it you may as well change it. Also, taking the O-ring out may damage it, and it's just easier to pop in a new one than to try and reuse an old one.
Neil is dead on in his post. The Apeks kits cost around $20 and include all the O-rings and seats and 1st stage diaphragm. There is also no reason for the high price.
At the minimum call them and tell them that you want them to replace:
All the O-rings with the ones issued by Apeks for that reg.
All 3 seats
The diaphragm in the first stage.
If they want to charge a lot of money for this, ask them to itemize the charge.
They SHOULD also look at the exhaust flapper and make sure it's sound. Apeks suggests replacing it in their service manual, but curiously the overhaul kit doesn't include one. They are usually fine to just leave in place, but they should be inspected.
It really pays to find a good shop to do your service. Even if this means that you have to send it in by mail.
It sounds to me that this shop doesn't know much about regs, and didn't really want to do the servicve. They figured that for $200 it would be worth it to them.
Heck, at that price they could afford to send it to another shop to do the service and still turn a nice profit.
Good luck with it, and let us know how it turned out.
