there really isn't a market for an anthropological social science for either business or government. That is an overstatement. There is a market, one piece of evidence being that this year's EPIC (Ethnographic Praxis in Industry Conference) will be held in Tokyo. The problem is that I know nothing about how one becomes one of the people who find jobs in that market. I have signed up to attend EPIC, partly to see what I can find out.
Rick, your question is a difficult one for me to answer. I have never made a living as an anthropologist in Japan. When my wife, who was then a Ph.D. candidate in Japanese literature at Yale, got the grant that brought us to Japan in 1980, I was an unemployed anthropologist who had spent the year before we arrived as a research assistant in the Yale Computer Science Department AI Project. That, and a list of names to call from one of my wife's colleagues, who had worked in advertising in Japan, got me a job as an editor for a small translation/corporate communications company doing daily translations for IBM Japan. That led three years later to my being hired as an English-language copywriter by Hakuhodo, Japan's second largest advertising agency. When I left the agency in 1996, I was able to move to The Word Works, Ltd., the translation company my wife had founded 12 years earlier. As it turned out, the timing of our move to Japan couldn't have been better. I was employed at the agency and The Word Works was founded just before the bubble went up. We rode the wave and were well established when the bubble collapsed.
You face a very different situation. The Japanese economy has spent nearly two decades stagnant or in recession. The low birthrate has created a crisis for higher education in Japan, as universities scramble for students and face increasing pressure to become more businesslike in their operations. Looking for an academic job? I haven't done that in years. I suspect that it will be a hard row to hoe.