Unfortunately, Chinese-made 95-rated masks are about the only thing we can get here. I would imagine it's the same in Japan? Of course, I've got a handful of the original ventilated 3M N95 masks from before the pandemic hit and I believe those are made in the U.S. (or at least not in China) but those are no longer available to civilians. The Chinese KN95 masks are the only readily-available "good" masks you can find, although certainly not for cheap. If you visit most hospitals in non-ER settings, this is what most staff are wearing. They can be had for around $7/mask retail, and I was able to get in on a bulk deal for around $1.50/mask. These are pretty much what I wear all day while at work and out in public. I throw mine in a UV-sanitizer when I get home and try to get a week out of each one.
The Korean-made 3M N95 masks are nice and should be good quality, but they're also ventilated, which means they're banned in most healthcare settings. I keep a couple in my work and personal vehicles but unless I'm going somewhere I consider really risky, I generally avoid wearing them to avoid getting dirty looks. I've got 200 of them but I figure I can still use them for chores and cleaning once this pandemic is over.
But even the NIOSH-certified N95 masks, which are about as good as you can get stateside, are now made in China. I managed to get my hands on four cases of those, which I'm basically saving for any overseas travel that may come up. And those fuckers are pretty expensive, if you can get them at all. I've only ever seen them being used in hospitals, so I keep my stash hidden and/or locked up.
It's remarkable how this pandemic has triggered my OCD tendencies and brought out my inner-hoarder. I hope this is all over soon.