Don’t know what they do today but you used to be able to have them with a FFL and permit.
An uncle had a Vietnam-era (?) pistol they called a “hush puppy” that was factory suppressed. That was a POS though. It’d made a better cudgel than a pistol, the way I remember it.
Some family friend had a suppressed .30 cal rifle of some sort. All I remember about it is that the suppressor was at least three feet long so the entire rig was more like seven feet. The other thing was that it fired some sort of wacky hand-loads (so it was subsonic, I guess) and wouldn’t eject the shells right… always jammed up some way or other.
Should have been more specific and said that I think they should make sound suppressors available for purchase by all law-abiding citizens WITHOUT having to jump through BATF/Treasury hoops! The ONLY reason I don't have any "goodies" (sound suppressors, full-auto weapons, short-barreled, etc.) is because, even though I am among the law-abiding, I DO NOT want to highlight myself to a government that may be friendly to me now, but persecute and prosecute me as a owner of such weapons in the future.