I've been collecting C&R for years, I kind of lost track of what was going on in homebuild land.
Yeah, that’s been a very long time. There are multiple options now. Imbel was making new, not recycled receivers, though. Imbels do still go for a bit of a premium, but it’s $600 or so, not $1000+ now.
A brand new DSA receiver is $449 retail. http://www.dsarms.com/FAL-SA58%20Upper%20Receivers/products/13/
Entreprises start at $349. http://www.entreprise.com/fnreceivers.html
You can even get one for an “inch” FAL from them, as the L1A1 receivers.