Every year many people in the Americas or Europe are tempted to buy used or new radio equipment from Japan. "Should I?" they wonder. "Is it ok?" The answer is...sometimes it is, sometimes it isn't.
The general decision framework can be divided into Tranceivers, Receivers, and Accessories (antennas, plugs, etc.). It is rarely a problem to purchase either new or used equipment in the "Accessories" category. Many antennas; handy little wires, connectors, shunts, plugs, sockets, and so on are available in Japan that are not available elsewhere. Buy to your heart's content! However, don't moan to me about shipping, custums duty, taxes or tariffs; speak, instead, to your bureaucrats, administrators, and politicians.
Receivers and Transceivers are a different matter. Yaesu and Icom have stated in the Japanese press that components in their Japanese-version HTs are not 100 percent identical or similar to HTs made for the rest of the world, and have repeatedly stated that any wideband modifications (MARS, MURS, CAP, etc.) made on a Japan-market HT will render the radio useless. Is that true? Is it Bravo Sierra? It's your money, Jack; just don't moan and lament when you discover that what was spoken was the truth. Remember, too, that the Japan Bandplan is not the same as the bandplans in Europe or the Americas, and that the bandplan within Japan is not set in stone. I have a wonderful FT-897D, in great shape; I run voice, CW, and digital modes on it all day (and night) long, with zero problems. Unfortunately, it was made when the 40m band in Japan started at 7.000 and stopped at 7.100. The band has recently been expanded to 7.200 but the radio can not be modified to transmit past 7.100. A similar problem exists with the 80m band. Do be careful. If it were me, I would pass on Transceivers.
Receivers are tempting because the bandplan doesn't care where you are listening. However, do be mindful of power requirements (for Tranceivers, too, if you must gamble in the Transceiver market). Japan's power grid is unique becuase it is split into two different frequencies: 50Hz in the east (which includes Tokyo and environs north) and 60Hz in the west (Osaka, Kyoto, and southward). The reasons for this are historic -- for whatever specific reasons, in the nineteenth century Japan bought 50Hz German generators for Tokyo and 60Hz generators from the U.S. for Osaka. The Power map of Japan is a mess: 500kV transmission lines smashing into transmission lines carrying anywhere from 187kV to 275kV bumping to DC transmission lines, with dozens and dozens of switching stations, substations, Frequncy Converter Facilities, and AC-DC Converter Facilities, all ruled over by ten large regional power companies, from Hokkaido down to Okinawa. Beware PolitiSpeak in Japan: "market reform" simply means that one of the ten regional power behemoths can sell power at outrageous prices in a district far from its home. [See the page on Life in Japan to understand why this is so.]
You should be ok with newer Receivers, as all new electronics in Japan have switches allowing easy changing between the two different standards, and a very, very small few are made for international use with full general compatibility. If you are buying a new Receiver, however, why buy it from Japan, with its higher base price, fluctuating foreign exchange rates, and expensive shipping, along with import duties, and possible tariffs? It makes little sense. Used Recveivers can be tempting, but then power considerations come into play, along with the exchange rates, shipping, duties and tariffs. If you must play in the used Receiver market, be careful -- and when everything is turned upside down, as often happens, don't complain that nobody told you about the pitfalls. At any rate, good luck and ganbatte!