TT sells their rack and Zega case through KTM. A bit spendy, but well made and lightweight, the new Gobi? (IIRC) cases, the plastic ones you see on the 950, can also be used with this TT 640 rack. I am not a fan of how wide the Zega cases are on the bike, and would run two 35L Zega cases, versus the 35L/41L combo that KTM sells.
The 640 is amazing in what it will haul, and how fast it can still chug along with a heavy load, but IMHO, unless you just doing this kinda touring on occasion and not as a rule, the 640 is utterly the wrong bike for this. Heavier Loads just kill the sweet handling and feel of the bike when off the pavement. The 640 ADV is my favorite all time bike for exploring, and not much else in the category interests me, but in considering a long multi month tour, I am rethinking using the 640, primarily because of this.
Österreichische Motorräder und deutsche Autos. Wie wundervoll kann das Leben sein