Kos is a very nice island. I suppose you are going there through Pireaus by ship.
I was in a greek island some days ago and what i can say is that you will be in trouble finding DECA from Organon. The pharmacies (even in Athens area) usually have the 50 mg DECA from Organon and not the 100 mg ampules.
In addition, it is very difficult to find NORMA deca. Probably you could get from Kos, Testoviron Depot but only one to two boxes. Do not expect to find Primobolan Depot. Finally you should not have any problem buying Clomid (ANFARM) as well as Proviron (both of them in small quantities though).
If you have a day or two to Athens let me know.
Nagasiro.