Personally I would leave it because of the expense of getting to it. Can't believe they didn't change it when the belt was done.
As long as you check your car and have a look for any signs of a coolant leak and/or noise from the pump. First sign of a leak get it done immediately. If the pump fails your coolant isnt being cycled therefore the engine doesn't cool and eventually overheats and cracks the head or blows the gasket.
Ok, I'll have to ask my friend to check it as I wouldn't know what I'm doing or looking for lol.
Thanks.