I bought a brand new one of these two yrs ago. In October I received a carpenters tool kit I had bought. It had one of these sets included with the other tools. It was missing one die also. Must be how these things are.
Btw I bought the new one from Rio-Grande, it works great. New cost was $36.00, I think it is worth every penny. Instead if drilling holes in non-ferrous sheet, you just punch them. It is very clean and neat. If you need to drill holes like this, $20 is a great deal. The dies can be bought at RioGrande as a set of 7 hole sizes for $17.95. I think they wear or break over time. The body of the punch is heavy duty and will last you forever.
Chilly