Ghost Ops RPG is pay what you want until end of June on DTRPG.
https://www.drivethrurpg.com/product/246179/Ghost-Ops--A-Modern-Day-Covert-Ops-RPG
I've never grok'd it before, and haven't really had much interest in modern spec-ops RPGs, but after a glance it looks easily hackable into different settings (near future or post-apoc). Can get it free right now, so may as well check it out.
Awww shit! Mack Bolan or Able Team, or better yet, the Rat Bastards here we come!
(been waxin' fondly over those old manly novels lately for some reason)