If you throw a rock, you’ll probably find a AR15 manufacturer. I say this, having been one when I had my FFL 07. The market is saturated. So to Gibbz Arms credit, they approached it differently.
Rather than rehashing the AR receivers by changing the trigger guard or something, they actually went about creating a side charging rifle. Personally, I’m not a fan of side chargers, but I will say, the Gibbz Arms G4 Receiver Set is the best executed side charging AR15 I’ve seen.
You can find the Gibbz Arms G4 Receiver Sets here.