Water Pump job cost? V90

[DKL]

I have a small amount of coolant leak every day for a while. Have determined it to be waterpump. Could be gasket, I suppose. An indi repair shop has quoted $500. Not including T belt. Just had that done. Seems high though. The part is only $150 retail. This car has 87K miles. It should not be the pump, I know. Would a bad thermostat cause a leak in this area as well. Would it cause enough pressure to force fluid out of the weap hole?

Thanks
DKL '98 V90