Hope you dont plan on taking it back..
Watch the show "locked up abroad" on NatGeo. Its all about people that try and bring drugs back to the states and get caught in the airport and have to serve 5-25 years in a foreign prison
Seriously, roids are not that hard to get. I posted this soo many times already but its very easy to get gear locally....why go throught the hassle of taking gear back or ordering from overseas? Maybe because I am in Cali which has a rep of having roids.
What I would suggest is, instead of taking a trip to Istanbul, take a trip to Los Angeles. Once you get here, find the nearest Golds Gym and get a 1 day pass. Walk up to the biggest guy and ask him if he can hook you up with some juice. They will not punch you in the head and will be more than happy to help. This is how I found my source and I now have over 5. And I go to 24 hour fitness....there is WAY more juice heads at Golds Gym