Jan,
The steel described below is AISI/ASSTM W112, JIS SK2, DIN C 125 W, Werkstoff #1.1563. Budderus Mills is one of the producers of this steel. The mang. in the formula you put down is a hair high as the formula calls for .10 to .35. The carbon range is 1.20 to 1.35 and the Si and chrome fall right in place. It's one of the higher carbon W-1's. On the low end of the spectrum is C70W1. The same formula with .65 to .74 carbon. I'm thinking that C70W1 with .15 to .20 Vanadium would be an excellent Sword Steel.(In my humble opinion)
Scott, I would love to have what's left of that file tested. Send me a piece if there is anything left.
Nicholson File
1.23%C .37%Mn .21%Si .16%Cr .09%Ni .04%Mo