I got about 20 years of weekend use before it needed a 'rebuilding'. The place I bought it from is still in business but I'm not near there so did it myself.
If you can't find local to you.
parts are available from Hydraulic Parts Supply in Sawyer kansas.
Some good guidance in some older threads on Garage Journal if you rebuild it it yourself. https://www.garagejournal.com/forum/showthread.php?t=302034
Looks for posts and threads by "Hiball"
When you clean up your jack you might find some more identification clues.
