the K bikes run their front brakes in a far more sensible fashion than the Airheads generally do (in my less than humble opinion).
Anyway Motobins are having a sale and are selling the top hose and the bottom hose for a K100RS for 20GBP each - braided stainless steel covered hose. The metal pipe that runs down the steering head can be obtained cheaply from a wrecker, or could be made by a hose place cheaply.
Anyone interested can infer that the K100RS front end is in the process of being fitted to my R65.