BRAKES HARD - BOOSTER OR VACUUM?

[es61@prism.gatech.edu (Eric Schumacher)]

I have an 86 4kCSQ with a very firm brake pedal.  It started several
months ago with 1 yr old pads and rotors (still plenty of wear left).  I
asked a local shop to check it out & they say "see the dealer."  I asked
the dealer's shop foreman who said it was likely the vacuum pump and not
the booster.  I croaked when the parts department wanted $700 for the
pump.  They also said it was non-servicable/rebuildable.  Has anyone had
the same problem?  Braking is not diminished, just needs lots more foot
presssure.  Also, engine runs fine (idle and at speed).

Please include suppliers if you have some solutions.  

Eric Schumacher
es61@prism.gatech.edu