A genuine vas6056?
Thats a serious commitment to brake pipe flaring!
If I absolutely have to replace a line I just use off the shelf 3/16th copper / kunifer with stock M10x1 fittings, and a vice-mounted flare tool. If the line runs free along its length (or in a vulnerable area) I'll cover it with adhesive-lined heatshrink. If it is clipped in place then I'll paint it with POR.
If you are able to source the real black-coated metric pipe then that would be quite interesting. I'd definitely need a better flare tool to handle steel lines though.
I agree we are in an extremely frustrating situation with parts, entirely of Audi's making as they appear determined to kill off the older models. Audi Tradition is simply a marketing exercise to promote the brand and not (as we naively hoped) to actually support their loyal fans. I refuse to accept defeat though and will keep as many D2s going as I can for as long as I can