Acera,
I admit that using 30 round Bren mags in a FAL is a bit of a novelty. But it is a kick to go through 30 rounds without changing the mag. The original .308 Bren mags can be used in Inch FALs. Some company took these mags, filed down the front tab or lip so they will fit into Metric FALs, and refinished them in gray. I believe I got mine from DSA. Mine have worked great in my FALs but some report having problems using them
The .308 Bren was produced c. 1958-1991. It is therefore likely that all of the mags for this rifle are pre-ban. I doubt if any company produced mags after the rifle was discontinued.
Drakejake