I still think it's better to ship through a FFL rather than doing it yourself.
Just accept that the FFL fee is the cost of doing business,and you're willing to absorb it. So many guys act like that's a deal breaker and the end of the world to eat a few dollars. It shouldn't be.
Your FFL will verify that it's going to a legit FFL recipient and address. That's added protection for you.
In my locale, my FFL will add a charge for a gun sent in by an individual. He would much prefer that guns are sent by a FFL, and I agree with him. Occasionally, he would receive a gun with no idea who sent it and no idea of who it was intended for. He then had a hot potato that he couldn't properly log in,and had to wait for the buyer to show up and get it all straightened out.
Just because it's been done by others at the Post Office, is no reason to violate the law.