Firstly, where is it leaking from? If its from the gasket seals around the water pump body, you can use rtv sealant to re-seal the water pump.
However, if it leaks from the pulley bearing, I'm afraid you will have to change the entire pump.
need some help deciding should get an anti-cat system exhaust
i am worried that i will lose back pressure since my r34 is triptronic? i dun want lose the low-end...but if i boost up turbo, it should matter right...