Finally heard back from Victor at US anodizing and this is his response. Sort of contradicts what is in their FAQ:
Since you live in NY (Not sure on the law there regarding your request, a pre-ban state), we will have to ship any completed receiver to an FFL holder. If you provide us with an FFL copy, we will ship the completed receivers to them! Other wise we cannot service your receivers.
So this is a no go for a "sterile" firearm. Looks like the finish will either be BBq paint or duracoat until I decide if I want to try my hand at home anodizing.