That hasn’t been my experience. I have purchased three basses from Japan, each of which were over $2300. The Japanese music store (Ishibashi Music) simply charged me the price of the bass plus around $200 shipping. My basses passed through the US customs in Chicago without incident (or taxes) and arrived VERY quickly through USPS.
I cannot say the same easy process will occur with every Japanese seller, but I can say that Ishibashi has been absolutely stellar with each of my purchases. Not only did I save money, but the basses were all in excellent condition. Judging by the feedback I’ve seen from others who have bought basses from the same store, I’d say my experience is the norm for Ishibashi.
If you’d like a more comprehensive account of what I did to make my purchases, feel free to IM me.
Incidentally , what type/model of bass are you looking to buy?