what formats are you looking for? It is kinda tricky to find certain brands and formats in Turkey we are somehow digitized , I would suggest that you get some with you in any case.
There is one shop I regulary order and stock film, they probably have the best prices but you would find some films in other places as well. I have to find the adress to them I order by phone.
There is Pamuk ticaret , and as I am told there is saatcioglu somewhere close to their store (I have never been to those stores) which is ilford's distributor.