Hi, thanks so much for the ID!!
Attaching photo of the Crack here, it is very close to the handle and mainly on one side. As of yet seems to be holding well. Not sure if something like that can be fixed but it is a nice maguro otherwise. It is 440mm long and has a saya as well.
I'm also curious of what type of steel it is, but not sure how to find out. I did find info on the shop thanks to your ID of the knife, but their online info is not very in depth
Thanks again for your help with the kanji! Wish there was some kanji book or something for knives and stones!
Jeremy