ken ca
Hi Rafael,
I mentioned pre war Norris irons so I stupidly assumed everyone would know what that meant, sorry. They are 3/16" thick parallel, probably just high carbon steel blades, often blades of that era were called "cast steel", again, I think that is simply high carbon steel.
Brass Brazing looks bad because of the color match, but I bet a scarf joint with silver solder would be far less visible.