Keep checking PWS “cannon parts” (blems) I’ve seen plenty of mk107 mod 1 and 2 uppers on there a lot lately. There is a mk107 mod 1 available on there right now. The Diablo (mk107 mod2) was my first PWS, i stuck a law folder on there and it was a great truck gun and looks cool af, but the .223 Wylde version I had suffers big time from low muzzle velocity and effective range (~100 yards max) due to the short barrel. I loaded up on Speer gold dots which still expand reliably down to 1500-1600 ish fps, but I ended up selling it a couple years ago, so there is at least 1 floating around Vegas. I am currently running a PWS mk111 mod2 (11.85”, 11.5-12.5 seems to be the sweet spot) and also their mk116 mod 2 both suppressed and love them. If I ever get a sub 10” barrel ar15 again it will be in .300 black out.