Was going to say the same...
The part number is 383931, but is no longer on eBay.
What is wrong with what you have? Spin tubes are easy to find, as are the bushings to restore the drive pulley, etc. Most often when I have used a whole drive assembly was when I wanted to save time and make a quick one for one swap, but that is an expensive way to go.
If the restoration you're working on is missing the drive altogether, a 383929 / 285897 will supply all you need except the pulley, which can likely be had elsewhere and swapped.
Gordon
P.S. - just remembered you are working on a Canadian machine...that explains this unusual configuration.