When buying a katana, its origin is a matter for controversy. Some people do want to buy katanas only from Japan. But you have to know that a Japanese saber is either a real Shinken (sharp katana , carbon steel) or an imitation which is resolutely a copy (not sharp).
So, you may find some very good iaïtos, not sharp (alloy blade) in Japan. But sharp sabers at a relatively cheap price (less than 5000€) do not exist. Thus, the Japanese forge skill is preserved within the whole tradition among the lands where it has risen.
Keep in mind that if you haven't the means to offer a genuine Japanese saber (more than 6000€), some well-known brands and sites are often a good alternative to find katanas of fair quality. So you will have fewer possibilities to be disappointed because of the finishing, the assembly and the power of cutting.
You can find our sabers from Japan at the Nihonto column. For any request relating to a specific blacksmith (Tohsho), please contact us.