By Ayla Jean Yackley ISTANBUL (Reuters) - Hundreds of Syrians and other migrants thronged a small park in central Istanbul on Wednesday, hoping for a last chance to reach Europe before poor weather makes their favoured route from Turkey to Greece too dangerous to undertake. "It is time to go, while the door to Europe is open," said Zopir, 20, who fled the Syrian town of Deir al-Zor three years ago and now wants to reach Europe before his wife, eight months pregnant, gives birth. "I am afraid, but I am ready." Zopir scraped together 8,000 euros ($9,000) for their trip, which begins in and near the park in Aksaray, a working-class district of Istanbul, by hiring a "dealer": a front man for smugglers who help refugees reach the Aegean coast.