Power steering pump

[fastegg]

My '98 LS400 210,000km, full Lexus service history until 175,000km when I bought it..
When you put a screwdriver on the power steering pump and up to your ear you can hear quite distinctly a ZZZZZZZZZZZZZZZ sound and at idle, a faint thump----------thump---------thump that you can just feel on the screwdriver. I was thinking of a reco exchange pump from the states, several mobs doing them between $90-$160.
Basically my question is, is there a problem going this way ? I'm mechanical but only have one working hand so doing it myself isn't an option. So yeah, has anyone heard anything about American exchange pumps ?
PS: Without a screwdriver on the pump/ear, it doesn't sound apparent so I'm not concerned at present, I just know its there

 

[BlackUZZ31]

quality is shit on the china pumps, better off getting the $45 seal kit $10 baring and getting someone to "give you a hand"

ZZZZZ sound is normal thump is probably baring and it will start to leak out the weep hole on the bottom and kill the alternator