didn't principality get changed to 75 sometime back?
Personally, I think a single knight is probably enough.
Of course the way I read the item it's very specific as to what territory is being described without naming it. A simpler version would just be to waive the pop requirements for TN.
Duke Sir Lassidor Vandolini, KC, BOD treasurer, Imperial Exchequer, Defiance member, BoC of the Kingdom of Vega