147 steering pump

Hi just had my mot pass with advisory oil leak, when i thought was a bit odd, when i thought about it i had topped up the power steering fluid at the weekend, so when i checked it was nearly on empty again . Mechanic has now told me the power steering pump has gone , so if anyone knows of one going for a 2002 147 , please give me a shout.
Su x
Also is it still ok to drive as long as its topped up?

Haven't got one but..... have a slight humming / vibration noise when maouvering slowly and sat still, are these the symptoms of a fubared pump?