Used Harrell's dies come up for sale every now and then, and they sell well. For the PPC there are markings that indicate how much they size at the the base of the case. In that respect they are standardized. Instead of using a reamer to make the dies, the cavities are bored out with a boring bar on a CNC turning center. Dies are made up, and on the shelf so that when they determine what your chamber requires, it is already there and waiting to be shipped. Because of his marking system, buyers of used dies can have a fairly precise idea of what they are getting, and are therefore able to buy with some confidence. I believe that his are the only PPC dies that are marked in that way. I get your point about it being a used barrel. If someone you know shoots a PPC, and uses a Redding die, perhaps he might size one of your sized cases that had been measured as fired and then you could measure it after sizing to see how much (if any) his die reduced the diameter of your case. If the sizing was good, you could buy the same die. In addition to Redding, Hornady and RCBS make bushing FL dies for the PPC. The advantage of the Harrell's die is that you know that it would fit, and if you needed a different one for a new barrel (possibly cut with your own reamer so that all subsequent barrels would take the same die) there would probably be a ready market for it.