Palmetto State Armory has some awesome deals on barreled upper receivers including BCG and CH. Round 220 buck depending on what ya want. Blem mid length are 200. I just ran 6 mags in my PSA pistol upper in no short order and it functioned flawlessly. Locked to the rear etc etc.
I am a big "ya get what ya pay for type of guy" but PSA has made me a believer in their products. For my simple range applications it more that does the job.
Great 4th of July Sales. God Bless America!!!