Well, I think we´ll never see a NF-5 fly again in NL since it´s simply to expensive. And the RNLAF would never sponsor somethng like that with their cramped budget.
But if a plane would have to be picked I think the F-5 would stand a better chance then the F-104. Simply because there are still lots of flying F-5´s in the world and parts would be cheaper.
And AFAIK the NF-5 is also cheaper in fuel consuption.
But a mission impossible if you ask me.