(Repeats story first issued on Sept 1)
* Syrians slip across borders en route to West
* Western Balkans struggling to cope with numbers
* Refugees face extortion, abuse by mafia and police
By Valerie Hopkins and Tsvetelia Tsolova
PRESEVO, Serbia/SVILENGRAD, Bulgaria, Sept 1 (Reuters) - O liver Ivanovic's patience paid off. Shortly before midnight, on a hilltop in no-man's land ...