1999 Toyota Camry water pump/ timing belt

I have been told that my timing belt is attached to the water pump. My pump has a leak and will need to be replaced because not replacing will cause many more problems for me. My quote is $350.00. Resonable? I know that "replacement" parts at a Auto part store are $25.00 for the belt and $33.00 for the pump. So labor is essitaial 300.00. How long should it take?

Thanks,
Janette Harris