I have a leaky PS pump dripping on my newly installed,costly alternator.I'm quoted about $1,100($675 pump, balance labor) to replace it by Lexus dealers.One shop warns me not to replace a quality factory Lexus PS pump with a low cost aftermarket,used junkyard or rebuilt one from an auto parts store.I find on EBay new aftermarket pumps with resevoir for around $200.Has anybody reading this post had good luck with an aftermarket pump? A mechanic warns me only a true Lexus PS pump can correctly deliver the proper (high) fuild pressure, long term, to the somewhat sensitive/demanding/costly PS rack.Like our 96 LS 400 but hate the power steering system design.I replaced the high pressure hose already, myself, using an aftermarket hose and so far so good. I replaced the pump oring under the resevoir but it my leak is from the pump body.Any advice on the pump issue? About 135,000 miles on the car.Thanks.