I had good luck on EBay buying one 2 years ago. I started searching there regularly for a 10Kpsi combination. What I found was usually Good quality with poor descriptions for items were the cheapest. Best sellers were the CAT cylinders that I was "Watching". I bought a cylinder that is very similar in size to a 12 ton Enerpac. I had previously acquired a nice Enerpac 5 ton push cylinder with a 10K pump. A decent Pressure Gauge and a few replacement fittings to marry the parts together was all it took. I assembled it and put it up against a Shop press with a Gauge that read in PSI and Tons. A few readings at various pressures got my gauge close enough for pressing sprockets and clutches.
I got one off ebay a couple years ago for about $100, as I remember. Had a plan to make a load--control bushing puller/installer for JD tractors, but haven't ever got to it...
Watch ebay for Enerpac or Simplex units.
well i have bought all of my enerpac and even a cat 100 ton setup from Craigslist