Honestly? That looks like an Austrian STG58 bbl. assy. (it was one of the best FAL barrels ever made, I've got one on my FAL, made by Steyr) with an FN commercial upper and an Imbel lower... A parts gun. But a damn fine looking one at that and made with quality parts and most assuredly prior to the Cliton fiasco of 1994 when FAL's went to shit save for DSA.
There are details on that rifle that just aren't present on modern FAL rilfes. And they ran out of new Steyr barrels a loooong time ago.
If it turns out not to be a collector (I doubt it is one) you can always keep it as a good shooter or even upgrade that rifle into a more modern version. They can still hold their own, though they have some brutal recoil and aren't much of a long range platform. They are, however, a reliable and solid fighting rifle.
This one started out life very much like yours though it was Austrian parts on a DSA receiver set. Cerakoted inside and out, I removed the carry handle, installed a folder, an Elcan 7,62 optic and DSA full top rail/optic mount, SDN6, oversize controls and a 2 stage adj. Jard trigger. Some other tweaks have been done and there's a PEQ if it needs it. This ain't Dad's FAL for sure. With a 4lb trigger it can do around 1MOA but in all honesty it has random fliers that can open this up to a few MOA but I think that had to do with the handguard being loose, which has since been fixed but not tested. Austrian mags are best, IMI is good and FN is good --try and stay away from the rest. Can't speak for DSA's new mags but if they're made on the same machinery as the Austrian 20's they'll be great. Korean knockoffs wouldn't even fit mine. Some say the DSA Bren modified 30rd mags don't work, the curved ones, but I have four and they all work great.
Oh the times I've tried to sell this rifle, wasn't gouging, just have too much in it I guess... FWIW, I saw a competition where it was FAL vs. SCAR17 and the FAL beat it's ass in all but the few accuracy dependent tasks. I guess that made me feel better about keeping it.