Definitely nothing that fast. Right hand, only way they came. Any lefty you see on the road is a conversion. Still on the fence about building it out
Threaded wise, I would vote Autococker threaded detents. A detent that's commonly available at pretty much any paintball pro-shop.
Empire feedneck threading is ICD threading .810 i believe.
Also, look at availability. Ccm feednecks suck. Huge, no lever and cor what they