Not your typical mukimono (or is it), a solid carbon steel but not a honyaki?
I just noticed this new knife that Keichi of BluewayJapan has listed. It is a Yusuke solid white steel single bevel mukimono. It does seem to have a concave back, so it should be a true single bevel knife. Although it is a solid steel, but there is no claim that it is a honyaki. Listing seems to claim similar HRC, 60-61, to their gyuto range though.
Click for bigger pictures:
The listing says it is concaved on the back, and indeed from the pics it seems like monosteel.
For sure not honyaki otherwise the price would have been different.