We had a bunch stuff for AR uppers kicking around and thought 'what the hell...' and built a few up. These are all built around genuine mil-surp over-run component (except for the hand guard which was made by the C.H.Ina Co. but, they are actually pretty nice in person and have M-LOK rails included...) The barrels are the same ones we have been selling for years with M4 barrel extensions and are all chrome lined. Trap doors and forward assists are installed, they are just waiting for a charging ahndle and bolt to complete them.
Built up and ready to go, there are only a few of each length. If you require a custom length barrel unit just email me (or better yet call) and I will do my best to answer you quickly.
Found here :
https://dlaskarms.com/products/ar-15-upper-receivers
We can also built these into complete rifles starting at $799.99.