Welcome. Have you tried to get the rebuild parts at NAPA yet? If it's not leaking fluid yet, it might just need the check valve cleaned/freed up.
EDIT- I see that Auto Specialties filed a Chapter 11 bankruptcy petition on October 3, 1988. I don't know the outcome of it all, but they may very well be outta business.
If the jack hasn't suffered from some sort of breakage and the hydraulics haven't been damaged by rust, you may be able to resurrect it using O-rings, etc. from another brand/type jack.
But if it's a narrow, short, low lift floor jack, another jack could prolly be bought for less than the parts will cost to fix this one. I would only mess w/it if it's a sentimental favorite or if it's a good jack.
Last edited by cobalt327; 03-18-2011 at 08:40 AM.