The Nissan Path

On my 01 SE Pathy with 90k miles I was getting a squeak which sounded like my brake pads. Took it to the mechanic and they said its the brake booster. Apparently the booster has gotten a leak somehow and the squeak is caused by air going in or out, not sure which and that it is dangerous to drive the car beacuse it is losing vacuum and could result in loss of braking. They offered to find a remanufactured one with my permission and install for $375 (from the dealer the part is $800) They say master cylinder is fine. Any thoughts on this condition? Other remedies? They are ordering the part and can install it by tomorrow 4-21-09. If you have a better suggestion I need it soon! Thanks in advance.

So I stopped by the shop this morning and the service writer wasn't there and talked to the mechanic. Turns out the mechanic didnt feel it was that big a problem since they really couldn't produce any symptoms and they gave me my car back, cancelled the part order, and sent me on my way. As far as I can tell I was getting screwed by the service writer who was trying to make some money. It is an unfortunate incident that seems to occur more often than not. By the way .... I was at n NTB in norcross, ga.