I have finally booked my Korean award! But that was not easy at all, some (hopefully) useful advice for booking a Korean award.
1) Calling Flying Blue (toll free in the US or in the Netherlands) was not very useful, they found no or - once - very limited availability. Sending them an email with my request, resulted in excellent availability.
2) The taxes for my award when booked by Flying Blue in the Netherlands were much lower than when booked by Flying Blue in Canada (both converted to Euro).