Hi Shane-does your old bearing have a tapered inner race? If so it is the same as on my Model 60. The only place I have been able to source this bearing was a long time ago from Olcar Bearing Co. in North Carolina. He has no web site but his telelphone number is 910-693-3324. His name is George Bachleda. I also have a copy of an "The Old Partsman" article that covers an alternative bearing that a fellow Australian found. I can scan it and send it to you if you would like. Phil
Rear wheel bearings are available from AA Bearings in Melbourne, He had them in stock last year when I got mine, front and rear, reasonable price too. They advertise in restored cars.
On a side note, I'm chasing for my spare W5 engine oil pan, side covers, front timing cover, front pulley, oil pick up and flywheel, and manifold if anyone has one spare.