Yeah, that price is outrageous... I would DEFINITELY contact the BBB... you might, in addition, try to get some other estimates from other more honest shops to positively prove that the first place ripped you off.
There is an Exxon station in a town near me that is run by all Vietnamese mechanics with very limited English skills... and they tried to tell some lady that a new muffler for her Mercedes would be like $250. She was just about to go for it when I happened to pull up for gas (the old "get $1 here to get me down the road to the cheaper place" maneuver) and hear what was going on. The mechanics were NOT happy when I told her the real deal... so the lady told me she would report them the BBB the moment she got home.