Currently there are no CRLs for The Armorer, however don’t let this stop you in doing this build. Start a WIP post and keep detailed updates with photo references of the screen used armor and props. The key to a canon build is to recreate, as close as possible, what you see on screen. Take time to study photos and learn the small details.
As to this helmet specifically, it is probably the most accurate we have so far. There are subtle differences in the key slots and where the horns are placed on other helmets. This one specifically has been updated. One thing to consider with the Raw Cold Cast option is it references brass, I’m not sure brass is the most accurate metal. Last I knew the seller was possibly updating this to be more accurate but you may want to ask before choosing this Cold Cast option. But the basic raw cast option and this helmet specifically should be fine.