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.
Dear All Altezza Owner out there, i need help from all of you, im urgent looking for a Auto Altezza Half Cut,with fully body part include everythings except engine and gear box.. If include also will consider about...