Just out of interest, I just priced up a revenue tkt on ITA, as I would have suggested this as a way to determine the taxes & surcharges. e.g.
Code:
Fare (A1): JL SHATYO BLPX1M fare (rules) CNY 4135
Fare (A2): JL TYOSHA BLPX1M fare (rules) CNY 4135
Tax: People's Republic of China Airport Fee CNY 90
Tax: JL YQ surcharge $160.40
Tax: Japan International Passenger Facility Charge ¥2040
Total for 1 adult passenger: €1050.00
Which is about €156 for the extras.