the co is just short for company as in Wallace Berrie & Co....although after my embarrassing effort earlier in this thread maybe you should wait to get confirmation from Richard again.....lol
Wallace Berrie had the distribution rights in America (correct me if I'm wrong) so all of the smurfs with those markings were released specifically for the American market.
You may be right, but there are an awful lot of those in Belgium as well, so people have brought them here after a vacation, or they were sold here too originally. I'm going with the second option!