If you build AR15s for sport or recreation these are parts that you will be interested in.
No complete firearms or lower receivers that would require an FFL.

Bolt Carrier Groups
All BCGs have MPI bolts and carry a Lifetime Warranty.

https://www.spicetac.com/Toolcraft-556-NATO-Black-Nitride-BCG/
https://www.spicetac.com/Toolcraft-556-NATO-Nickel-Boron-BCG/
https://www.spicetac.com/ar15-parts/bolt-carrier-groups/

Upper Receivers
https://www.spicetac.com/aero-precision-upper-receiver-ar15-assembled/

Barrels
Barrels in 223 Wylde, 556 NATO, 300 Blackout and 308 Winchester calibers.
https://www.spicetac.com/ballistic-advantage-11-5-5-56-nato-carbine-length-ar15-barrel-modern-series/
https://www.spicetac.com/ballistic-advantage-11-3-5-56-ba-hanson-carbine-length-ar15-barrel-w-lo-pro-performance-series/
https://www.spicetac.com/ar15-parts/barrels/

Raptor Charging Handles
https://www.spicetac.com/radian-raptor-charging-handle-556/

Pistol Braces
https://www.spicetac.com/sb-tactical-pistol-brace-sba3/


Buffers!
https://www.spicetac.com/ar-15-heavy-buffer/
https://www.spicetac.com/ar15-h2-buffer/
https://www.spicetac.com/ar15-h3-buffer/