Prior owned swage dies, like anything else, should be bought from someone who knows exactly what they are selling so a full description can be asked for and received, or otherwise a money back guarentee is in the cards. As far as who made these dies go, it could have been some of the 20 or so makers in the business during the 1960s-'80s. RCBS was one of those makers... as a matter of fact that firm got started making .224s from .22rf cases during the '40s. Some of those "reloading press " dies ( and this is what's being sold here) soon wore out and would make oversized ( or out-of-round) bullets now. You would have to make a few 'test' bullets with the dies to see how they work. And, don't let all those parts cloud your judgement if you don't have any idea how or why they are used. No parts are a better deal that a bunch of worthless ones, especially if you are going to spend $100s on them. Bottom line: ask the seller all the questions you have and if you don't get the answer you were looking for, pass on the sale. Do not assume anything.