The impellers are just force-fitted onto the drive shaft and can often "slip" and then give up the ghost on you entirely. False economy not to change it while in there. Pattern pump from Motor Factors less than £20
Got the head gasket and cam belt done for£180 but mechanic said head wasn't worth skimming cos it's got some corrosion. Drives spot on for now but not sure how long it will last so if head gasket goes again, the car will be goin to the Punto graveyard as it's only worth a few hundred quid.