The only things from Halo 5, that I’m aware of at least, are the assets from the Waypoint app. The only thing worth using from there is the bodysuit, which appears to be at game quality, or just slightly less.
I have it rigged and in Source, but it still has some issues to iron out before I release it.
I also do have a few of the helmets from the app, but they aren’t worth using at all due to the terrible texture resolution (256 x 256).
So presently the best option is to adapt Halo 4 armor to the Halo 5 bodysuit.
Are you talking about on here or elsewhere?