Floor jack - rebuild, or buy new?

My trusty, 20+-year-old, heavy steel floor jack is not lifting as it should. Bottom of the piston looks wet, like the seals are leaking.

Seeking advice from the hive mind - is it worth rebuilding, or does it become scrap at this point? Any pointers on sources for new seals, or other thoughts on hydraulic Viagra to help the old jack lift as it should? Just add more hydraulic oil and hope for the best?

Brand is unknown - Chinese made, probably bought at Costco during the Clinton administration.

Having 2 just like it, that act the same, I'm interested as well. 
Hey, they have both been abused over the last 20+ years; my dads was even left outdoors more than in! They've done well!

I would use this it may be less expensive than a new jack

I had similar issues on my floor jack last summer...picked up new seals from Lazzars floor jack repair and rebuilt it.  If they do not have a kit for your jack, they have guides you can use to measure what you have and order replacements.  Cost me like $60 to rebuild it but probably did not need all of the seals I replaced... Not too terribly difficult but was a little tough putting the end cap back on the cylinder.

I volunteer with the local high school auto shop. Instructor was tossing a blue point 1.5 ton floor jack. I couldn't bear it so I took it home. A few o rings and 45 minutes and the thing works fine. I'm torn as to whether to give it back or just keep it. I'm going to offer it back but I don't think they care. Off point, he says they don't even really teach engine internals anymore because motors are so reliable that rarely is there any reason to open one up. I hate that he is right. But I also hate that the first option was to throw away a good jack. 
 

'what sucks is that I really want a long reach but can't justify it now that I have two working jacks. 

Also used Lazzars- the kit was $39, but I used less than half of the stuff they provided. Great to have it all, and I'm certain the actual cost was like $2 but they knew what I needed.  

I've rebuilt one of my floor jacks a half-dozen times over the years.  Plenty of o-rings and it's good to go.

It's messed up.  If you can fix it, you win! If you cant' fix it, well it was messed up anyway; you have nothing to lose.

(As an aside, I teach highschool mechanics, and all my level 1's go through the rebuilding of an engine.  For a couple reasons: 1. graduated licensing means few kids even have a license, much less a car. 2. my school demographics are largely high income and low income, not much in-between, being able to rebuild a beater to keep getting to work makes sense. 3. It teaches kids in a controlled manner that there is a WAY things work, and a WAY things go together.  My purpose it to build confidence in working on vehicles, and you can better diagnose when you fully understand what's going on.  But that's just my opinion.....).

I say "Fix It!"

(and do a video on it)

Thank you for doing that, skinny. I wish we focused more on repairing than replacing. Our guy is awesome, and maybe I caught him at a moment.