97 Buick Century Custom
3.1l v6 w/ 4spd auto (only engine/transmission available on this car)
92k miles
Long story short: Car starts overheating, coolant is low, coolant is added, coolant is low again, coolant is added again, coolant is leaking out from under water pump pulley.

This is not a picture of my car, it is a picture of a similar car with an arrow pointing to the water pump. This is just to confirm that I'm not a complete idiot an dit is, in fact the water pump.
Two questions:
1: How much will I expect to pay for a new water pump?
I did some google searching, and I found a few sites offering water pumps for $25-$35. This seems far too good to be true, and I'm either getting something crappy and generic, or I'm getting a different part altogether.
2: How long will it take to replace it?
Please tell me it's not more than an hour or two.