Hey, folks -- Does anyone recognize this waterstone? The grit level on this stone is well north of a 16,000 Shapton glass stone, and even my 30,000 Shapton doesn't polish a knife or plane-blade edge like this baby does. Trouble is, the day's coming when I will need to replace it, and I can't recall where I got it. I'll be grateful if anyone out there can help me identify the maker.