there is very few people with guns and i think only afew people in the whole country with pistol licences, i guess no more than some 1000snds or so with hunting licences, maybe a little more.
im not totaly sure .
there is a custom and production knife market though, and there is 1 or 2 japanese knife forums and a knife magazine.
the main problem is language..... as few people speak english or a willing to if they can ,
it is the same with japanese companies, bloody hard to deal with as any dont have any english speaking employees and rely on agents to sell to western countries .......
the best thing to do is ask some japanese knife makers about what shows are the best , there is several in japan every year.