how much should it cost to replace a water pump in a 2004 chevy malibu classic? Is the timing chain linked to the water pump?

Its a convienient shop (next to my job) and they priced it at $550 - they stated it was tied in with the timing chain. So I wanted to get a second opinion. I have dealt with them before and they seem a bit pricey, but again it was convienence. Maybe I will look elsewhere. Thanks much

Thank goodness I have a wonderful friend that did it for $37.00 Part was $21.99 and coolant was $15. It is a pretty easy thing to do. Save your money and watch a video, you can do this yourself.