Brake booster

[Kevin Smith <kevin.smith12@domain.elided>]

I think the brake booster on my 86 spider is going out!
The pedal has been feeling weird lately, not like a master going out.  Sometimes very stiff, sometimes ok.
Noticed yesterday that when depressing the brake pedal the idle went away almost to the point of stalling.  I 
replaced the boost cable with a piece of heater hose until I could get the real thing but no change.  Also noticed a 
sucking sound when depressing the pedal.
Usual parts sources list a new one for $330!  Can they be rebuilt or is it a generic brake part that I can get from 
a local parts house?
Any help in diagnosis and parts question will be appreciated!
Guess I will not be able to autocross Sunday :>(

Kevin Smith
Nashville (2001)
86 Spider
87 Milano (in the paint shop)

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