It's likely made out of tool steel so after hardening/tempering would probably be in the 50 RC range? Hard, but drawn back enough to not be brittle. Something like this is very easy to make if you have a metal lathe. I usually use O-1 or W-1 material and small parts like this can be reliably hardened with a MAPP or Oxy/Acc torch and tempered in your oven. I have a small ceramics furnace that goes to 2200 degrees F for larger parts or something I need to control the ramp on. Now, is it worth your time to make it rather than buy it, that's up to you. But if you have the machines, it usually means you don't want to be tied to the supply chain. Looks like a nice little machining project for this winter.