David Weaver
I think LN uses whatever their heat treater will do. AS I recall, they stopped using O1 as an option because either their heat treater stopped doing O1, or they were using a second one who quit.

You're right, it's not expensive. The best of the steel around (presto, starrett, etc) is only a little bit more, and it's *really* good, even out of a can forge and quenched in a paint can.