"I was thinking I could use the BH stablisers but when on its side does the motor still run?
No, the oil in the sump would drain to the lowest part of the engine when it's lying on it's side. No oil in the sump means no lubrication in the engine.
Even when you right the machine it would be advisable to let it set for at least a couple hours before attempting a start up. If you have to move it to a level area, tow it. Personally, I'd let it set for a day, if possible.
As far as righting it...at least a full sized pickup, especially if the back hoe is rigged to the tractor. A robust winch might do the job too. It depends on the size of the tractor, I should think.