The Hughes Amendment blocks civilian purchases of selective fire AR15, which prior to 1986, were available to them. Hypothetically speaking, you're a law enforcement or non military government entity. You're purchasing selective fire AR15s. Who is/are the company(ies) manufacturing and selling to you? You're not buying or receiving surplus military equipment. Because obviously not all of the myriad of AR manufacturers are making selective fire lowers. The majority are semi auto only servicing the civilian market. I'm working on a piece demonstrating selective fire ARs are not available to general public.