You are flying to Istanbul, Turkey? I have never been to Turkey.
OK, I guess you mean EY/IL. I do not know gentle-ease, they have pampers and everything else that they have in America, just not in all stores. They sell deo., aluminum foil, zip-lock bags, BBQ sauce, toilet paper, white-out ...
Actually, if you use Baby Spritz, it could be they do not have here. I can't think of much else offhand. Some things cost more, possibly Gerber baby food.
Where are you planning on living?
Hatzlacha!