PART I. The Basics
The easiest way to order from Japan and have a very good chance of a successful, satisfying purchase experience is to order from one of the reputable retail chains here. All of these compete on reputation and generally will go out of their way to ensure you get a high quality, well set up instrument.
A number of people here have ordered internationally with great success. The bass usually leaves Japan within 24-48h. Japanese shipping is amazing; you may see customs delays of course, but I think most people have not.
On to some recommended vendors:
In my experience the one with the best web experience is Ikebe Gakki. (Gakki means “musical instrument”, you’ll see it a lot.) They have an outstanding and easily searchable web store, fantastic selection, and good customer service. I have bought several instruments from them both in their stores and via the web, as you can indentify specific instruments you have tried on their web page:
Ikebe is nice because they have a very localizable web page. In the upper right of the screen, you can select English and you’ll get pretty solid translations of everything:
They have an International Order link on each instrument page you look at:
Kurosawa is another excellent chain, actually perhaps a little higher end than Ikebe, but they are pretty similar.
This is their online overseas ordering info:
Here’s their online shop, which actually has somewhat bilingual headings and titles but is nowhere nearly as nice as Ikebe’s page, you’ll need Google Translate:
I have never personally bought from them but they are one of my favorite browsing experiences. I think @JerryP did buy from them.
Ishibashi is another big chain here with excellent instruments. I have bought an instrument from them before (in-person, not online) and had a good experience. They have a separate page for international customers, I am not sure how the selection matches their domestic offerings however. In fact their international offerings mostly appear to be used instruments, which is not a bad thing; it’s an interesting twist actually, as there’s some deep values in there, and an excellent used selection:
Here’s their Japanese domestic site, if you want to browse with google translate and see something you like, it could be worth an inquiry:
Shimokura is a huge chain here. I would not describe their web experience as great, but they do have info on international orders and they do have a great selection:
I have bought an instrument from them and had a good (if brief) experience. I would say they are the most pro forma of all the shops listed here, not great but not bad.
That list should get you started. There’s others - I really wanted to list BigBoss here (ESP’s retail store), for example, but I didn’t see a good international link for them. I can help with future questions if anyone has any.