I don't think these are knock-offs...the collector whose personal property auction I bought these from had had them in storage for a long time and a lot of her pieces still had price tags on them and were never used by her at all. They were at a bottom of a box of her things.
I should phrase that better: it was actually a family of three lifelong collectors, mother, son, and daughter. They accumulated 3 buildings worth of items that sat in storage for a very, very long time. The pieces that were outside of boxes were often in rough condition with years of cobwebs, rat dung, you name it in and on them. The stuff that was nestled into boxes was in much better, nearly pristine condition. Not to say that we don't all get fooled by repros once in a while...but I'm pretty sure they knew their stuff, and she also had other really old, authentic items that I've verified.
What is Nori? Also, what are the underglaze flaws? The only underglaze things I found were the brushstroke marks that I thought were by an inspector, artist or worker...I have some early 1900s porcelain china that has multiple intentional markings like that (also the color of the paint doesn't match any colors in the plate, like it was intentionally used for marking).
Thanks all for your input!