So, thanks to the staking on my M&P 15 I really screwed up the buffer tube when my wrench slipped a few times while taking off the castle nut. Does anyone know who makes the buffer tubes that S&W installs on their guns from the factory? I have found a few on eBay who offer a made in USA mil-spec tube in 7075 aluminum for $25 but that almost seems too cheap. I'd like to stay as close the factory as possible though. Going to call S&W in the AM and see if they can help me any way, too. Not sure if S&W outsources their's or makes them in house. Searched online for hours with no results so I was hoping someone on here could shed some light for me.