able to lift about 50 tons each - I need four. Any leads?

Are you using these for re-railing or a major jacking operation?

We were able to borrow (4) 100 ton capacity hydraulic jacks (with a 6 inch lift) from a local construction company. (They used them for bridge work) They used a gas engine powered pump and were controlled remotely which was a great safety feature.

We used them to lift EL&WB No. 1 and 2 while we built the new roadbed beneath them. No. 2 weighs 188,000. The jacks had no problem lifting her once we got a firm jacking pad built.

If this is what you are looking for try a local construction company that does bridge work. Good luck!