I know of NO optics company on the planet that sends out OPTICS parts for self repair.
ALL of them require you to send your optics in to be repaired.
Your Nikon Binos I am willing to bet are going to be fixed under warranty at ZERO charge to you. Does not get any better than that. All its going to cost you is a few bucks for shipping.
Now would be a good time to be thinking about having a set of back up Binos. I have about 20 pair of "back up Binos" . Acutally I have a addiction to Binos but that is another subject.