The price of Japanese household appliances not manufactured in Taiwan is absurd in Taiwan. Sometimes second hand products in Taiwan cost more than new items in Japan, for example, in case of bulky items like electronic piano.
I once paid tax for importing electronics (speakers) when my friend sent me without knowing the tax, and I ended up paying around 15% of the full price for receiving the item.
In terms for headphones of Japanese manufactures, buying them in Japan saves you a lot even compared to buying in eg US and EU.
For example, I got my ATH-AD2000 for around 450 USD when they were the cheapest, and this model was the flagship model of AT. If you like the sound, it's a bargain.