I thought I had the 'Robbedoes' magazine with the first appearance of the Smurfs nearby, but I somehow can't find it now. Instead, I have two other pics of early 1959 that I thought you might like to see.
The sad news is that this week, the very last edition of Robbedoes weekly magazine has appeared, after 67 years and more than 3500 numbers. The French language version, Spirou, keep on appearing (more than 100,000 copies every week), but for me, this is quite sad, as it is the origin of the Smurfs, and I collected them (I have almost every copy from 1960 on).
Advertising for the Pirrewiet (Pirlouit, Peewit) puppet from 1959, the first one together with the Marsupilami to be available: a Johan and some Smurfs would follow later
The first advertisement using Smurfs, appeared in 1959, while 'The magic flute' wasn't even finished yet! It's an advertisement for a game from Robbedoes magazine combined with Black Cat coffee.