I have been using Tacticool Arms for transfers lately and last time I was in there I mentioned I needed to get some engraving done for NFA items. Mike said it was something they were starting to get into but had not actually had someone take them up on their service. I was a little skeptical at first as these are like tattoos for your babies and mine were going to be their guinea pigs. I have say, I was very happy with the way they came out. They were able to meet the depth requirement and were very reasonably priced ($35 each). On the suppressor, they decided to go a little deeper (.005) as I am having them cerakote armors black. I showed them some examples of how I wanted it to look and where I wanted it on each item. They hit it spot on. The turn around time was very quick also. As far as I know, they are the only guys up in NoCo area that actually offer NFA engraving services.