Back in the 90s at least, up around the DMZ, there was a market for rat and snake soju (literally a bottle of soju with a rat or snake in it. Think tequila worm only bigger). These were smuggled from the DPRK, and were an exclusive item up around the Munsan area. Given the millennial predilection for bath salts and tide pods, I would think an entrepreneurial nork could sell a whole lot of the stuff in the USA at a handsome profit.
Only “entrepreneurial nork” s are extremely rare and lack the freedom to do this....and likely would be jailed & tortured for doing so. Strong incentives against entrepreneurs.....
PS: My daughter lives & teaches ESL in Seoul........