If the 21 Years Old thing is putting you in a bind, just buy a complete lower already in rifle configuration, that should satisfy the regulation.


Here is my low buck build:


$492 as shown in the pic.
I just picked up some Magpul XTM rail covers that aren't in the pic for $20 so that makes the total $512.

After installing a Troy low pro gas block, I have put 1K through it, both steel and brass and can hit 4" steel all day with the crappy Magpul sights.