Only a state with its resources could produce something like that. That is basically an act of war for a state to engage in such a thing.
OK. So why aren't we - with our far superior technology, dropping planeloads of counterfeit NK currency across the peninsula?
Seriously. Drive the NK economy even further into the ground.
Maybe it will prompt Kim to adopt the SK Won, then (frankly it would be worth it) Kim can be promised a fancy oceanfront Villa on the Sea of Japan with all the movies and babes he can handle - and the dismantling of that Marxist regime can begin.
It would beat the alternative.