great to hear from you all the way from Argentina!
Alley Oop indeed was published by Thomas Kalak. As far as I am aware, it was not for sale anywhere (maybe except in a few skate shops) but photocopied and distributed via mail. Since issues 5 and 6 are from 1987 I would guess it also started around that time, maybe a yeare earlier. There was a similar effort by Stefan Oerder called Backflip.
In more recent times there is a full color magazine published by Marta in Stuttgart called Doy Days Magazine.