alloro/steve, thanks for the clarifications!

While the ac system is opened, would it be adviseable to replace anything else aside from the o-rings... such as the dryer (or is it an accumulator - my impression is the dryer/accumulator have to be replaced regardless when you open it up), clean/flush the system, etc?

i know labor charges vary, but what do you think it might cost to have a shop do this (assuming minimal part replacement)?