An interesting paper by Park and Jeon (2023) mentioned that South Korea imports about 78,000 crayfish as pets a year from 2018 to 2022. They describe 34 species imported.
I was surprised to see that marbled crayfish are not one of those species listed as being in the Korean pet trade at all. Usually they would be not only widely available, but one of the highest risk species.
But this YouTube video strongly suggests marbled crayfish are available in Korea.
Reference
Park Y, Jeon Y. 2023. A study on the import status of pet freshwater crayfish and potential invasive alien species crayfish in Korea. Korean Journal of Ecology and Environment 56(3): 242-249. https://doi.org/10.11614/KSL.2023.56.3.242
