Cambelt change is simply cambelt changed, though a lot of people recommend the tensioners and pulleys changed at same time, hence cambelt + tensioner kit.
Water pump might as well be fitted at same time, as its only gonna cost about £50 extra, but you will have to ask for that to be changed. Though if water pump breaks not long after having not replaced it, you'll be looking at the whole cost again, as cambelt needs to be removed to get to water pump iirc.