That has been discussed by many people before. And from what I've heard, it's impossible. But I think it can be done. But don't take my word for it. I don't know what I'm talking about.
But that would be cool. Not the dumb colour one, but the grey-green military one.
It is possible to make the screen darker, brighter, filter out certain colors and some other stuff by putting a transparent plane infront of the players camera like I did with my nvgs. But it's not possible to make everything black/white with this method. It's also not possible to color certain things black and others white (clientsided), which would be required for proper thermal vision.
Famas barel is a little thinner
Not everything is always supposed to be 100% accurate.