I walked into an engraving shop in the mall at the intersection of 95 and washington st in woburn and they did a rifle for me in 10 minutes for almost no money. No need to ship it anywhere.
Anvil Arms is a company out of Florida that does laser engraving, and also makes AR lowers. I've interacted with them a few times, with bad results. The owner, Jon, seems to have a pretty negative attitude...
Orion Arms does CNC milled engraving, and as far as I can tell, thats all they do. I know several people that have had engraving done by them, and its always come out as expected. They are completely unrelated to Anvil.