I agree that any of the die brands will do a good job. I use dies from all manufacturers. I have an RCBS set for my Krag, but the Lee set is good, too. In fact, the Lee set is a 3-die set because it also includes the Factory Crimp Die.

At others' suggestion on this board, I've been doing Partial Full Length sizing with my Krag: I back the die out a full turn rather than screwing it in an extra 1/8 to 1/4 turn. This sizes just the neck. About 3/4 of the neck shows the sizing. If you only have one Krag, this will save wear and tear on the brass.