Mine have all the same markings. And I don´t know which one is the 11th
About the history of these smurfs (both trafficsigns and other objects) I really don't know too much about them. I have them since 1980-1981(more or less) and my parents bought them for us (me and my twin brother) at the store where we usually went all saturday to buy them. So the years dated at SCCI letters are correct
In the first years of 80's there were very frequent campaigns of road safety for children, in all schools but smurfs were not the most popular characters...The great succes of them began with hanna barbera cartoons, two-three years laters, so I don´t think they were used as promo for "children"
I have my doubts about the signbearers smurfs with a ladder and a bucket together, but I am sure all the others were sold in Spain