If it ain't worth a thousand (between relatives at least), I don't know about you. You'd sure not get much for anything less.
Just a warning. Don't tow the tractor to crank the engine. You risk tearing up
the rear drive which is a bronze worm gear not designed to both push and pull. You've
got to hand crank it, and you will exhaust yourself unless you have it tuned perfectly.
They used to have 6 volt drycell starting batteries in the old days. This was to replace
the magneto while starting. You could probably use a rechargeable batteries from
one of your tools, 6 to 12 volts max. WARNING Don't connect any voltage to the flywheel
magneto, or you will demagnetize it and make it nonfunctioning. Lots of after-market ignition systems were installed, and when the F became the Model N, they had magnetos with impulses, like all the other tractors.