Parmandur
Book-Friend, he/him
The only really canon info we have is that 3 were Numenoreans, and one was an Easterling. Pharazon was one of the Nazgûl in ICE MERP canon, and seems a plausible candidate, as do his son, Elendil's daughter, Miriel, Valendil and Theo.I the nine were given to the kings and queens of mortal men. I could see the boy of the southrons being a leader to get one, and perhaps Miriel being tempted into accepting one to restore her sight.