I have never seen it in a real military surplus shop in Germany nor in an internet shop in Germany, Scandinavia, Holland, France, Britain or the USA, and I play quite a lot in such shops although I am not really some kind of collector but rather a user of such equipment, I think relatively well informed nevertheless.
I assume that these pouches weren't yet sold to the civil milsurp market or went somehow a way that they stood in Danmark. The same with the surely with it issued big rucksacks.
Some countries simply keep the equipment for decades and if you want to get something from a rather small army you have quite a few problems compared to let's say US American, German, French or British military surplus.