I wound up just taking it as check-in luggage on my flight.
Beware that the various Asian airlines treat snowboard/ski equipment quite differently. ANA was happy to take anything up to the overall weight limit without extra charge. In contrast, Cathay Pacific and Singapore Airlines were charging something like $100. (Note: At least one of them wanted to charge per set, not per bag. They actually asked whether I had more than one deck/set of gear in the bag, because I was traveling together with my girlfriend and checking in only one board bag).