Cutting Down Brass Pin Punch....?

[dracozny]

I would just turn the end that is mushroomed until it looked nice. you can do this with a sander if you want. you already work hardened it with the hammer after all. it should last a good while longer as a result.

 

[JimDawson]

Thank you.
Starrett punches are very inexpensive, so they're worth buying. They have nice knurled steel handles on them.
I would like to make metric size transfer punches from O-1 tool rod. Is this possible?

Sure, it would just take some time and a little material.