All bushmaster flattop upper with 14.5" barrel and an AK brake. It has a detachable carry handle too. I got this upper in a trade with a reported 200 roundcount. I don't have any reason to doubt that count, bore is pristine, upper is in excellent shape. $400.
Bases on the discussions of this topic this is the threaded version AK brake, so you could put a phantom on it if you wanted to.
I'll throw in a fixed car stock too if you can use it, no pins. I can cut the fat out of it if you want or not.