You could check out this site...
Jobs in Japan: Jobs - Japan Jobs - Japan News - Japan Info - Japan Apartments - Japan Classifieds - Japan Forums
That could give you an idea as to what, and if, they're looking for foreigners in your field of work, and what some requirements may be.
Sorry I can't be more helpful, though.
Edit:
Jobs in Japan : Search jobs - Jobs - Japan Jobs - Japan Info - Japan Apartments - Japan Classifieds - Japan Forums
This is a search in the finance/business section.