Where to get car keys and door locks replaced?

Three work colleagues of mine all had their handbags stolen yesterday by some scummy lowlife prick, including their car keys, and want to obviously get a new key and change the transponder/immobiliser code, but also change the locks in the car. They've all got the same car (various models of 2nd gen Mazda 2,) and have been quoted around $2,000 for the work.

Does anyone know of a place that will do the work for less, or at all?