tubulars will knock down the price of a used wheelset by $100-$200. Also, with you living in Japan, shipping will be expensive, and North American buyers will prolly have to pay duty on them.

Kinda crappy, kinda unfair, but that's the market. I doubt you'd find a buyer who'd pay more than $250 total, so you're looking at $150 tops in your pocket. For me, if the wheels were sound, I'd just ride em or save them for the track, whatever. Nice tubbies are worth more to me than the cash I'd get for them, and worth more than the effort breaking them down.