The heyday of building FALs at a reasonable cost has passed. DSA is about the only company selling receivers except (I think) for Pars. Coonan imploded, so they're gone.
Receivers in private hands and kits are going up, maybe have plateaued by now, maybe not.
Keep in mind, the FN FAL was not designed to be a tackdriver- it's a minute-of-man rifle that's dependable. I've been following discussions on the Files for years and 2 MOA seems to be the best it can be.
If the challenge is what you're seeking, go for it. Seek out Gunplumber on the FALFiles and get his video or go to Arizona Response Systems and buy it (his company). And yes, GP may be an ass but he's probably the best FAL smith, at least that's still regularly in business.
Johnny(?)/Moses/CMP Armory in western NC- not sure he's still in business. Designed probably the best aftermarket non metallic mag for the FAL, suddenly had a bunch of problems and poof, not seen anymore.
Sent from my Pixel 2 using Tapatalk