Hi Mark,
I actually did ship them by airmail (JP post). It was something like USD 300 to get them sent to Switzerland. The rate applies to a 30 kg box, which is supposed to be enough for two guitars (Look out ! JP post doesn't accept heavier units). It took about 3 weeks to get them knocking on my door. No disease to observe. Just a pretty convenient solution as I had much more staff to carry back home.
However, in you specific case and with respect to the incredibly heavy administrative duty that Japanese officer carry out all along the shipping process, I would suggest you to take your treasure with you on the plane.
Here you get my suggestions about the best shops a vintage guitars enthusiastic should visit in Tokyo :
TC Gakki in Shin-Okubo (
http://www.tcgakki.com/) : If there is only one shop to visit, this is the one. The place I found the Casino, along with four other guitars for me and my friends. They have a stunning choice of vintage and used equipment (guitars, amps, effect units, ...), some you will probably never find anywhere else. Don't forget to visit the high end collection downstairs (small entrance on the right of the building). It will blow your mind off !
G-Club in Ochanomizu (
http://www.kurosawagakki.com/sh_g_club/index_eg.html) : Ochanomizu is the spot where most of the music shops are located. There are so many of them, spread all over the area. I suggest G-Club as the guys are fluent english speakers (at least the ones I met) and that counts. The shop is a favorite for some famous international musicians. Most of the stuff is new, but you might find some very nice bargains. I hesitated to buy a brown Riviera (same period as my red one but with a stopbar) just before leaving Japan. The guys at the Gibson Custom Shop (3rd floor) might be of great help to point out the place you shall eventually find your perfect toy. It would take you quite a long time to visit them all otherwise... and you will obviously have something better to do during your stay in Japan...
Well, if your wife gets sick and you have nothing else to do but hanging around, Shibuya area has many nice music shops as well.
I hope that helps. Please get back with some feedback and photos of your new babe !
Gabe