The Emerson 3/4 hp has a service factor of 1.5 which brings it to 1.125 and your hayward 1 hp probably had a service factor of 1.1 bringing it to 1.1 Seems like the Emerson 3/4 would be the stronger of the 2
As far as the leak goes, replacing the motor won't fix that, new seals should take care...