NOS Bendix Brake Booster
 

I'm not sure what year applications this is for, the instructions says "CHEVROLET -- ALL, EXCEPT 396 & 427 ENGINES".
This is a complete kit, power booster, nuts for booster, hose, intake fitting and a bracket.
Bendix Power Brakes part number 2506 136.
The only numbers I find stamped on the booster, other than Pat #, are 5853
$125 plus shipping
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