https://www.marstar.ca/dynamic/product.jsp?productid=86836
I purchased mine from there.
Marstar was selling a bunch of M16 lower parts kits a couple months back. Perfectly legal and common. You just don't put in the parts that don't fit.
Looks like they are still available. How's the quality of these kits?
Would it be a bad idea to install FA disconnector and safety? Switched into third gear, the latter will disable the disconnector and lead to an array malfunctions, right?