Man 1500 for a Head Gasket on a Toyota truck sounds like a lot! I had a Subaru and it was 1500 to do the HG's on it. They have to pull the engine to change them out and of course it's a common problem in older 2.5l Subarus. Big money for the places doing the work.
Problem with all Subarus, overheat them and it's head gasket time, cast iron block and aluminum heads.