The picture you posted is rather discouraging. You didn't say if it was stuck or not. Do you know? Even if it is stuck that's not necessarily the end. (The old tractor guys drag 'em out of the fencerows and woods all the time that are stuck and with lots of patience and their choice of penetrating fluid get them to turn over and eventually run.) I suggest you drain the oil. If water or antifreeze comes out first that will tell you something. If only oil drains then there is hope. I would spray/squirt/pour a generous dose of light oil in the cylinders everyday for about a week, then try to turn it over by hand. If it turns by hand then I would re-fill with new oil and try to turn it over with the starter, no spark plugs in it and the valve cover off. If it spins around good with no bad noises, binding, etc. and you can see the valves going up and down then I would try to start it. First disconnect the old gas line from the tank and use a temporay fuel tank/can of new gas with a rubber hose to the fuel pump. Old gas can cause the valves to stick. Basic ignition tune-up - and give it a try. Good luck.
