Once upon a time.... MRC offered one of their variants in a 300 Blackout (Ranch Rifle?) . I "think" with LH option. However, I could not find one with my meager Google-Fu skills. Left Hand Savage factory 223 rifle, plus, a 300Blk barrel swap from NSS would get you there for a little under $800...
Suppressed, subsonic, bolt action .300BO's are cool. Have one built on a RH Rem 600. Everyone who shoots it is surprised by how quiet it is...
