Highly sure it's centurion approved, pretty sure you just need the correct materials
(Screws, rivets, paints, lens) I believe you're allowed to have decals, aslong as it's ANH hand-painted style. (For that, you should try TK-4510)
*Edit* Yep,
Ears shall have three screws per side, one above and one below the ear bar and one at the base of the helmet.
Ear bars have four bumps only.Not three.
Traps/tears and tube stripes shall have the correct ANH TK details.
Correct 'Hovi mic' aerator tips.
Ear bars shall have only one bump painted in black (rank stripes).
Neck trim shall be of an s-type profile rather than a u-type profile.
Tears/traps shall be hand painted or use decals that emulate hand painted (with correct ANH TK details).
You should be good to go, if you follow those.
The rest is usually already detailed on the helmet, or self-explanatory.
I also recommend trying to replace the mic tips, with keith mic tips.