I have a 7-inch, piston upper in 6.8 SPC by Primary Weapons Systems for sale. Gen 2 chamber.
Only 50 rounds through it. I kept it as a home defense gun. Ran just a few rounds to be sure it worked.
Lower is Vltor, Noveske barrel and Noveske bcg with a PWS CQB flash hider. Functions perfectly.
Very few of these were made and they sold for nearly $1500 new.
Will sell for $1100 shipped.