My son acquired a bunch of these Valenite inserts (VIPV). Looking for a holder, I called Valenite (Walter) and inquired. They say they haven't made them in a number of years and had no answers or advice for me. Meanwhile, we have boxes of them and they look really good. Reminds me of a Dorian parting tool I have. Any advice on how to identify and find a holder or two?