Many European city/trekking bikes come with IGH and disk brakes, so they would fit the bill. I don't know how you feel about ordering the frame online, without being able to test it. Instead of a "full" mixte design, would a steeply dropping top tube do? Roseversand for example has some options, here's one:

http://www.roseversand.com/article/e...axi/aid:506255

Actually, if the steep slope top tube is OK, I think I've seen a few Kona frames with IGH and disks. Those would be available for you locally.

--J

[edit] Or, if a sloping top tube is still too high, how about a folder? Dahon Ios XL? [/edit]