Fred said
For $60 or $70 on eBay, you can get the KLOM tubular
key cutter. It is
similar, but not the same as the more expensive HPC TKM-90 "Pocket Cut-Up"
With a little careful work, you CAN cut them with a drill press.
The barrel key sounds like something that could be done in OpenSCAD, parametrically, and
printed in metal from Shapeways. For instance they have a 60% steel / 40% bronze mix as
well as others.