Looks a bit like the Berghaus Vulcan, which is made in China though.
But the BW KSK issues the Berghaus Atlas, that's why I guess that it's OK.
They are made like clothing in several sizes. If you are unsure about the right size it's probably worth to go to Salzgitter and try it on. The back isn't adjustable because they wanted it lighter and idiot proof.
Der Berghaus Rucksack MMPS Vulcan V ist das 2016 Update des bewährten Vulcan mit breiteren Schulterriemen und MMPS (Multi Mission Pack System)…
www.recon-company.com
An older version can be bought from the Dutch army used. The KSK changed the frame of the Atlas because the old ones sometimes broke. I guess the new Vulcan got the better frame too.
But I guess you will treat your rucksack a bit different anyway.
Berghaus Vulcan Cyclops 2Berghaus Vulcan with Cyclops 2 in cedar green The Berghaus Vulcan with Cyclops 2 is a serious expedition backpack for those who like to go the extra mile. A popular backpack for years, and was the standard for the Special-Forces of the Dutch Army. The Berghaus Vulcan with C
www.xmilitarystore.com
Räer in Hildesheim sells it used for a higher price but you could go there and choose the best one. They sit next to the railway station and are worth a look anyway.
Ihr Partner für Armeebekleidung und Ausrüstung aus Hildesheim. Schon seit 1920 gibt es bei uns neue und gebrauchte Bekleidung und Ausrüstung aus Beständen von Armee, Polizei, Zivilschutz, Grenzschutz, funktionell und verschleißfest.
www.raeer.com
They also sell the smaller Norvegian one, usually the cotton version as well as the Nylon version.
Norwegischer Jägerrucksack mit Tragegestell 1968 B Kaufen Sie Bundeswehr Bekleidung und Armeebekleidung vom Räer Hildesheim Bundeswehr Shop. Seit 1920: Sportlich - Robust - Räer!
www.raeer.com
And secret tip No1 is that Heim still makes the plain olive green BW Jägerrucksack in 1000 Denier Cordura.
I think it's apart from the Ortlieb packs the last German made hiking rucksack.
Brand new pretty cheap for a German made product:
Der BW Jägerrucksack Cordura ist ideal für Wanderungen. Durch das Cordura-Material ist er äußerst abriebfest und stabil. Neben dem Hauptfach bieten…
www.asmc.de