Having an Australian-made motor does not seem to me to be a functional advantage, but is very much worthwhile in collector-value terms if it is similar to the original motor. (My opinion on Australian-made electric motors, when they were made, is that they were a bit worse than the other electric motors made in those days, which by and large were woeful.)
I suggest you stay away from the merchant who ruined your double-row self-aligning bearing in future. Remember, that has to be a self-aligning bearing: a deep groove ballrace whether single or double row is useless for the purpose. The later, Rover-built 45s did use single row self-aligning bearings, and these were more or less successful.
