I used to have an original catted 314 that fit on my 2006 Viking QR cue. I'm trying to find another one! I don't think Predator makes the "Viking QR" joints for thew new 314-3's like they used to.
That's strange that they stopped making them. You could get one for a 5/16-18 thread and have someone bore the inner diameter of the threads to fit. Since the one I had got a cue with 5/16-18 threads, I'm pretty sure that's what predator did. I would call seyberts and see if they can help. I think seyberts sells the raw shaft and may be able to install the VQR joint on one.