Went to the Adelaide Custom Knife Show today, and while talking to a couple of knifemakers there (I know many of them from previous shows) one mentioned that a vendor there imports leather sewing machines, among their many other products. So off I trot to have a word with him and yes, they sell Cowboy machines. He said to call their head office tomorrow and talk to Bob, who handles the leather side of things. I left feeling optimistic.
When I got home I thought I'd check their website and the only machine they list is the CB3200, which is fine, unfortunately the price of $3700 is not so fine! Nor is $2900 for a hand crank head-only.
Looks like I'm back to figuring out the practicalities of importing a 441 clone (probably head only).