I've got one of these and would second it. It's claim to fame is it's size. It can fit a handgun and the handgun still be usable. I even had a G19 barrel cut and threaded into a G26 for one. I don't use it on .300BLK but it's because I have others. It'd be a fine SBR can for sure.SilencerCo Omega 9k can be run on both 9mm pistol and subsonic 300 BlackOut.
In a very compact package with decent suppression. It works nicely on a Glock 19 and 17
Dead Air Wolf and Griffin Revo 9 also shoot 300BLK supers. If I remember correctly, the Griffin requires a certain set up for short barrel BLK supers.As long as your only shooting subs there's quite a few options. If you want to be able to shoot supers the list is very short. Liberty Mystic or Silencerco Omega 9k come to mind.