If you are purchasing a new aircraft with Thales SMD displays, so I have been told by more than one Thales person, NVG compatibility is a zero cost option. If you read what I said it did not infer that they will exchange them.
As to the maintenance organisation - have to ask myself one day.
Altough that would only be part of the equipment required to be NVG compatible.
I think that is what I wrote isn't it?
I live about 2 km's from one of the few civvy NVG operators in Europe - no need to guess that one.