hi sages- bought first floor jack in 73 from sears craftsman. a 2 ton. made by torin which was then a japanese company. think it is now chinese. very good jack used it many times on my fleet of jalopies: wheels, brakes, clutch jobs, engine swaps. mostly frequent heavy duty jobs. never needed fluid, never leaked,and most important never slowly lowered the car while i was under it(figure leaking cylinder seals/o rings). started doing that in 05 after 32 years of use. at that time bought a 3 ton husky on sale at home depot and got a free 3 ton sears craftman when i cashed in my accumulated purchase points at sears. both new jacks have worked perfectly since then. all 3 are the single pump piston models and the hydraulic power units look very similar .never had a dual piston HF- dont like that design. would like to buy a power unit for the 73 or get it rebuilt. lazar has rebuild kits for many models including the 73. the only difference seems to be the extension length of the units ram. any one here know who could rebuild this power unit . all the sources i have tried have disappeared or perished. looked at the rebuild instructions on you tube and seems above my pay grade and patience reserves. anybody done here done this job? what think- can you help with a source. thanks tons oldduke