I'd look for a used one local to you--I bought mine new from a place that rents them for 200 bucks about 20 years ago,a few weeks after I bought it,a customer of mine at the parts store asked me if I knew anyone looking for shop equipment,as he was retiring and moving to florida--he sold his engine crane to a friend of his for 75 bucks,and it was not a cheap one--it was an OTC brand rated for 4000 lbs!.
He also sold a 2 post lift only 5 years old for 1000 bucks,he wanted more but not many people could move it--some lucky stiff with a borrowed ramp truck beat me out of that deal. Many times an engine crane gets used only a few times in many years,the cylinder is about the only thing that can wear out and they arent that expensive,so many of them end up at flea markets,swap meets,and yard sales for cheap money after the previous owner is done working on vehicles--I've seen quite a few go for less than a hundred bucks.Ask around at local gas stations or repair shops and body shops--if nothing else maybe they will rent or lend you one.If you can weld,I think you can build one yourself--I think you have the "Welders Handbook"--they have plans in there for one that uses a regular 12 ton bottle jack.It would be a good project for you,and you will get a lot of use out of it. /forums/images/graemlins/crazy.gif