Upper for SW M&P 15R 5.45 x 39

[refryguy]

Anyone have any leads on an upper assembly for the 5.45 x39 S&W AR?

I want a shorter one but I am having a heck of a time finding any.

[ANADRILL]

got mine from machingun tours...for 575$

[sniper7]

AIM surplus had them, I think they still do.
16" version...don't know if they carry anything different.

[7.62x39(4)life]

How is the reliability of these uppers?
What ammo are you using ?