gtg, do yourself a favor. Buy a new, top of the line F/L die. You suggest looking for a used on. Eh what? I'm guessing an $800 to $1000 rifle, maybe $600 for the scope on top, bullets running 30 to 100 cents a pop, and you want to cheap out on a tool that will last until after your grandson inherits it, sizing tens of thousands of rounds in the process?
A best quality, true, concentric die, that you absolutely know has not been abused, scratched, corroded, and isn't being sold because it is out of round is one of the most important investments a shooter can get. But if you want a cheap used one, go for it. btw, you can neck size with a F/L dies, just not the other way around, so next set of dies you buy for your next caliber, spend the bucks first on an F/L die, and get a neck size die if the rifle shows exceptional promise for accuracy, AND for loads you only fire for group. Having a neck sized cartridge that the bolt won't close on when you see Bambi's Uncle Buck will dissuade you from necksizing, I hope.