I orriginally thought dark green, after looking at all the reference pics and the most recent ones from the back, I think its similar to the darker metal colour on your mando helmet with a very dark grey over top to dull it down. I would do the same as what I did with the torch paint in a dark metalic colour then use some latex or mayo to mark out some scratches then spray (if you have an airbrush) a black/dark grey and maybe wash a little black, green and brown for spots of different wearing. then peel off the latex or mayo and you have your brighter scratches, then give it a controlled light drybrush to make a few edges look worn.
The pic with the explosion behind you can see the black back section and the grey with out the green tint.