Pretty low, I'd say. If anything, we'll get a reboot and not a direct sequel, but even then, Sony would have to find a developer that would be willing to resurrect an old franchise rather than create their own, which despite the Dragoons being totally awesome, would probably be hard to do.
I suppose they could build an internal team and force them to work on the IP, but that would be completely at odds with their usual method of acquiring new talent and then letting that talent do what they do.