I got three parties to level ten, including one of my own and no super sim ticket for any of them. I only have one in my inventory, and my couple needs a baby so the generation can keep going...incredibly frustrating.
I used to have the same problems and then I started watching all the videos and I now have 13 Super Sim tickets! I'm on level 22 so I don't know of you have more chances of getting them as you level up. I also got one when I organised a party and got it to level 10.