I made an interesting find at the flea market today. I found a whole bunch of Fix & Foxi magazines!
They were all from 1980 and 1981. In most of the magazines from 1980 the Fix & Foxi smurf was offered but there where no such offer in the magazines from 1981.
In the first number from 1980 there was another interesting offer. "You will get a fun smurf figure..." but the Fix & Foxi smurf is not mentioned so they probably offered another smurf.
Here are some pictures: