Yea, new GPO's are long gone. You might get lucky and find a used set. Maybe check Ebay?
Honestly never saw the need for them. I like my steel mesh grills better and there is less to mess with. Plus I can always throw the stock grills back in if need be since I didn't cut the factory tabs off the bumper. I get that people want a smoother look on the front end but then it ends up looking like a Grand Am sometimes.
Still running Street Scenes grills just to keep it different.