[gordon]

I'd expect rings or valves to be stuck, regardless of how free it seems to be. Since throwing it over is very hard on the starter, especially if it isn't exactly as it should be, I'd try towing it for a few hundred yards in top gear to check that the oil pressure comes up, and assuming it does just hook up fuel and a battery and tow it again until it's firing on enough cylinders to keep itself running.

Run it at a very fast idle till it's hot, checking all the time, then switch it off, check it, let it cool, and do it again the next day. With an investment of two or three days and a bit of towing you might find that it'll come right back into line without doing anything too drastic.

Gordon