Hi Ty, there's a one in two chance that your machine was manufactured right here in Oz...most of the British machines were all branded; most of which had it cast round the circumference of the outer hub. It's a pity that we don't have the Patent No.... that would give us the manufacturer.
I agree also on your reasoning for conservation, if you intend to use it,a good clean and grease, a sharpen and a roller that would be consistent with its age, a new handle main shaft would not only bring it back to original, but still rustic...Time will do the rest..
