mighty vac help

Who was the kind soul that offered me an older core parts only mightyvac? Im looking to get one like this 80's (06820?) model back into service and am missing a few parts, namely the top pressure cap, piston seal, main spring and the cap that keeps all that together...This is a cool tool but the PVC build material sucks. Cracks develop over time in gauge tower. I found the bones of this while cleaning out the top of my tool cabinet, thought I tossed it.
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