Assuming this is real, shutting down Rent-A-Hitman.com permanently would violate nobody’s constitutional rights.
It’s real for sure.
It features a cool T shirt. I emailed the guy and asked him if the T shirts were legit. He said they were. I now wear one around the house.
He did the site as a joke. He was surprised when actual requests started coming in. He turns them over to the FBI if they are serious.
That Chapter on YouTube does a video on in.