Hi,
The “Estate Gold” coating can only be applied to the Mark VII armor, and not the Mark V. The “Vermillion Fire/Flame/Wrath” which is basically the same but in red is available for all the armors (V, VII, Yoroi). I would expect a coating bought in the store to be available for all armor cores. I hope it is an oversight and that I will soon be able to apply it to my Mark V ODST.