I did some research for you and the Imbel FAL is made(assembled) by I.O. Inc..
I.O. Inc. has a TERRIBLE reputation for building low end guns and marketing them as top notch.
Now here is the catch. The price/value on this is pretty darn good. It's so good that I'm thinking there is something very wrong with the gun. If you have a history with the gun or really trust the seller then OK. If not, then don't touch it.
Most FALs on gunbroker are going for about $800 to $1800. The Imbel are going around $600. This guy is asking $400 with extras. To me, it sounds too good to be true.
The only other thing to suggest is if he will let you take it for a test drive. If it rocks then snap it up. My guess is he won't let you shoot it first.