Yes, someone makes a 240mm Nakiri. Yukihiro Sakai is a young blacksmith who was formerly with Nishida Knives. He has taken his knowledge of working with one of the purest forms of fine grain high-carbon steel to create his own material. Very few blacksmiths create their own material, but those that do the extra work, know the importance of proper technique to limit carbon migration from the core steel to the iron cladding. Takeda and Moritaka Hamono are famous for a reason.
White #1 is a highly reactive steel knife, unmatched for its sharpness.