I wrote I would report back once I had received my mixer(s). So here goes:
I received the first one of my two Kawai MX-8SR's today. This is a analog mixer with 8 stereo input channels, 2x effect ins/outs, headphone jack with separate volume control, and both 6.3mm & XLR main outs. It's a 19" rack mount, 2 height units high (it's approx. 48 x 9 x 24 cm). Each stereo channel has panpot adjustment, volume fader, effect 1 volume, effect 2 volume, and gain adjustment (L, M, H). Output volume is adjusted using the two main volume faders.
It's fully functional with very little noise, despite being second-hand and having been manufactured in the early 1990s. 😎 One of the input buses is a bit wonky, but it doesn't influence the sound. I cleaned it before testing.
It was part of a lot consisting of a 4 height unit 19" portable rack, a Kawai RV-4 multi-effect unit (which I still need to test - I know it powers on), and the mixer. I bought that lot for 3,500 yen on Y! Auctions Japan, described "AS-IS" (or as they say on Y! Auctions Japan "NCNR - No complaints, no returns"). With middleman costs it came to about 60 bucks, with shipping to about 200 bucks.
Expensive? Meh, not really. The mixer goes for over 100 bucks alone on Ebay, and the effect unit for even more. A comparable portable rack would cost me about 80-90 Euro...I probably saved about 100-200 bucks overall.
Of course, I did the research before buying, by looking at opinions on professional audio sites and reading the manual. Kawai makes quality gear that tends to be underestimated (quite a lot of their synths are cult). My Sound Canvas feels like a flimsy plastic Chinese knock off compared to this stuff.
On the other hand, I'm starting to get rather pissed off at the middleman service I use. I've been using them for years, yet lately they seem to be dropping the ball when it comes to packing stuff properly - minimum amount of bubblewrap + ignoring the specific packing instructions I gave. 😠 It makes me dread receiving the other package with the other mixer and a Kawai synth, because those don't have the benefit of a rack protecting them...okay, turned out not to be packed as asked, but decently enough for only a bent rack ear as damage...
Edit: Mixer #2 is also fully functional, despite one of the 6.3 mm output buses having had half the bus part broken off (the contacts are there) and looking somewhat beaten up. So thumbs up for Kawai's 1990s mixers.