Safe some money and try to fix this one yourself. If you don't really want to spend extra money and if the carb is working fine otherwise, then I would just replace the fuel bowl, metering plate, pump shot diaphram, and fuel bowl screw gaskets. Your leak is 'likely' coming from one of these spots. While you are at it, you may want to replace the primary gaskets as well.
Call up Jeg's or Summit, tell them your carb number and order some 'buna rubber' reusable NON-STICK gaskets for the above mentioned parts. Replacing gaskets on your Holley is super easy and will be easier if it is removed from the engine first. Good luck!
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