I am looking to convert a SA 9mm AR to a post 86 select fire.  I am an 07/02.

I would prefer one that has last round hold open.  I have looked at some of the major ones, but cannot find what I am looking for.  Are any glock mag AR9 lowers cut to M16 specs in the rear for a sear?  HELP?  Thanks.

I'm using a post sample DIAS in a CMMG Glock lower.  It is already low shelf so it was drop in with a DIAS.  
This is using their Radially Delayed Blowback design.  
I initially purchased their stripped lower their proprietary 9mm BCG/BBL RDB parts then when the Endomags came out, I switched to those on a regular M16 lower as I don't care for Glock mags.
Pictured below is how I use that lower now - for .40SW
I'm glad that I didn't drill it for an auto sear.....whenever I get tired of shooting .40SW or run out, I will probably sell that lower.  Much easier to sell it since it isn't a post sample.


Info on my 9mm CMMG RDB. https://c3junkie.com/?page_id=280
Picture below of how I run it now on a standard lower using Endomags or on the Glock lower above if I wanted to run Glock mags.

 QC10. https://www.quartercircle10.com/qc10-ranger-gsf-stripped-lower-receiver-blem-cerakote.html