Does anyone know any online retailer selling the S&W M&P uppers. Specifically, I want to purchase one of the piston models but I can't find a local dealer that seems interested in looking for one for me. I have an OR model and I've got dillusions about setting up a Pelican case with a complete set of both DGI and Piston uppers decked out with different optic setups, accesories, etc. Kind of my dream AR kit. Thanks for any help.

Yes. In fact there's an online retailer called "Smith & Wesson" that sells the S&W piston upper.

Product: M&P15 PS Upper Assembly

I'll try calling again tomorrow but the last time I checked they weren't available direct. On top of that, I would expect that I could find a better price somewhere else. I've never paid the MSRP on any of the guns I've ever purchased.

Would an M&P 15 upper fit on a Colt lower (CR6724-colt accurized rifle lower)?

Thanks