Baklava is a must try in Turkiye. Prices vary from 35 TL to 50 TL per kg, depend on filling. There were many places selling it all over Istanbul, from fancy restaurants in Sultanahmet area until small bakeries in Spice Market.
To bring it as gift for loved ones at home country, you can get some boxes on last minutes before depart from Turkiye via Ataturk International Airport. I recommend buying from Köşkeroğlu outlet (http://www.koskeroglu.com/) inside Airport Market, a discount store. You can find it easily after pass Metro exit gate, before enter airport’s departure area (few meters at the right side of entrance gate).
Pics taken from http://www.neredekal.com/koskeroglu-havalimani/foto-galeri/1.
Here is mine, I bought half kilogram of nut baklava = 20 TL (16 pieces):
I found a recipe online and wanted to try cooking it: http://chefinyou.com/2009/11/baklava-recipe/. Damn, I miss Turkiye already!