Summary - Front Passenger caliper froze - dealer charged $976 to replace - no other parts needed. How much should this have cost.

On my way into work this morning the front end of my truck started shaking violenty while I was on the highway. I pulled over checked the tires and made sure there was no ice inside the rim. When I got back on the highway the truck began shaking, this time when I pulled over I looked at the front rotors and the passenger one was glowing red. Forutunately I was only 2 miles from my regular dealer, so I gave them a call and they told me to drop the truck off.. When I got there I explained to the Sevice Advisor that it was most likely a hung caliper. Already late for a meeting they gave me a loaner and told me they would call back later in the day.