Originally Posted by FBinNY

Or, you might buy the 14mm nipples and a 2mm drill bit or reamer. Then by hand, deepen the counterbore for those shorter spokes.

I used to do this from time to time by putting a power drill or Dremel in a vise, and hand feeding nipples. It takes some touch, but then goes very fast. If you don't have a power drill, you can use a pin vise.

Note, reamers will offer better control with power, and twist drills are easier with a pin vise.