Yes, just do it, then you shouldnt have to worry about anything for another 100,000km, which isnt exactly going to come around quickly. Do the belt, idlers, water pump, seals.
I think people forget that the N1 water pump is designed for more track use. If your car is an everyday driver, or spends alot of time driving around the street, then get the pump that came with your car. Go genuine.
I was given an RB30 pump (at least I'm pretty sure thats what it was) by mistake for my 25, and it didnt fit, because of the slotted hole