We have a AR with the Tactical Solutions Upper chambered in 300 BLK. 
It also has a Magpul SLK Stock.

Tactical Solutions is proud to introduce the only 300 AAC Blackout upper which provides the versatility of a short barreled rifle (SBR) upper without the red tape and NFA paperwork. 30 Caliber Suppressors fit inside the circumference of a permanently attached shroud allowing shooters to attach a suppressor without significantly increasing the overall length of the rifle. The TSAR-300 is full auto rated with a mil-spec bolt carrier group. The Tactical Solutions TSAR-300 comes with a two piece free float hand guard.
This upper is mated to a Anderson Mil-Spec Lower and also has a Scope, and also comes with the Faux Suppressor.