Well, $800 to $1000 would be a great price to pay, but part of the Dealer price is a flush to go from the green antifreeze back to Dexcool (I switched out a few years ago), which is $150, new thermostat, new camshaft sensor (they said mine was partially detached and they recommended a new one for $80).
I had the intake manifold gasket replaced in 2006 by an independent shop who charged me $1100. That shop came highly recommended on this cartalk.com website.
One thing I'm hoping for is another problem to go away. When I drive in the mountains here say from 5200 feet to 7000 continuous climbing, the engine heats up. It doesn't heat up on the highway driving smaller hills and flats. Just when I go into the mountains. Am hoping the new thermostat fixes that problem.