a little OT, Determing AC motor ratings

Hi all,

I was lucky enought to get a deal on some equipment and one of the
motors is a single phase, 56 frame 208/230 vac motor. 1/2 inch shaft,
made by Marathon.

The nameplate is missing so I have no idea if it is a 1/2 to 1 hp
unit.

Is there some (simple) way to determine the motor hp or other
ratings that would lead me to know that ?

Sorry if this is too off topic, but I am at the end of me rope at to
searching the net on this one.

Dave