Belleville Disc Washers on Drawbar

I think I need to replace the belleville washers on my drawbar on my Acromax MX-16. This mill is a clone of a Matsuura MC-500V. My question is can I measure one of the washers and order them from McMaster or are these washers something special? I see that the washers come in high-carbon steel or chrome vanadium, any thoughts on which one to choose?

McMaster-Carr