I called three Canadian Brompton shops and none of them carry the part. This is the part since I somehow edited it away in the original message:

https://www.sjscycles.co.uk/hub-spar...sembly-hsa797/

All the Canadian shops want to replace the entire hub.

So now I have a message to some USA dealers. I guess I'll probably end up ordering from the UK. I can't imagine why this part would not be available in North America. I've done some Google and I'm not the first one to break the axle.

Would love to have the contact info for Dan Burkhardt. I'm in Ontario as well.

Maybe this is an opportunity to switch up the rear hub. Shimano Nexus or Rohloff?