I've got brakes!
Big Thanks to Johnny Cash for the inspiration to do this. I went with the Magura Series 225 13mm MC. Cost $87 from Amazon. A local bloke made up the hose for $70. Here's the result (please excuse dangling wires - I'm at the tail end of a refurb)
Only problem I had was finding sufficient room on the euro bars. My solution was to lathe up some bar extensions - friction fit into the bar ID and glued in with green Loctite. These were drilled and tapped for bar end mirrors. I like having the extra leverage on the bars, and the bonus is that there is less elbow visible in the mirrors.
Improvement in feel and braking performance is startling. Two finger braking does better than the previous 'grab a handful and pray' action.
I love this brake. Please accept more thanks, JC.