As to classical vinyl, of which I have a fair stack of the Japanese pressings, it's pretty much as described above...the pressings themselves are generally about as good as pressings get, but there is inconsistency in the sound apparently because different generations of master tapes are used, or there are just different approaches among the Japanese engineers that make the stampers. I would say that I've had generally good luck with the King Super Audio pressings (related in some way to Cisco), for what that's worth, and some really excellent EMI's. But I've also had some disappointing EMI's. I seem to recall that the few Columbia's I've heard were pretty darn good.
But the classical info doesn't get you entirely where you want to go. I have few Japanese pressings of jazz, but do have some Columbia Miles and Thelonius and Weather Report, and have a few Verves. (And I probably have some others that I can't recall.) Again, the pressings were all great. But the Thelonius (a 2 Lp retrospective) was edgy sounding. I seem to recall the Miles was pretty darn good. Same with the Weather Report. However, I would say that the Mosaic Miles pressings were more satisfying.
Like you, I've been searching for Japanese vinyl, albeit somewhat haphazardly, for some months. It does show up on Ebay, and that's mainly where I've found it since the 80's (the good old days...when you could go to Tower Records and find good amounts of it...sometimes).
I have gotten a fair amount too from a place called Audiophile USA, a website, very good to do business with, and you can search by country of origin. Come to think of it, that's probably your best bet...although Acoustic Sounds has some good things, too. That's the only place that I've found new Japanese vinyl. The rest is second hand (though not infrequently in great condition).
Send me an email separately if you want more info.
