I was thinking a bit more about your cost and know that where I live I was once quoted from a Ford dealership that the cost for replacing the water pump was about $1,600. With that said, if they pull the engine and take it apart to replace the water pump, I would think that a lot of those labor hours are the same hours that are required to replace the timing chain, at least it would seem so on the surface. The unknowns for me are the cost of the timing chain and all parts associated with it's replacement and potentially other labor hours that I'm unaware of. I'm simply pointing this out to ensure that you were billed properly and not charged for two separate jobs vs combining labor hours for both jobs.