BANGKOK/SURABAYA, Indonesia/HO CHI MINH CITY -- For Tresnayati, an Indonesian traditional cake maker from Sidoarjo, East Java, the effects of the war in Iran are very real. The plastic wrapping sheets she uses for her products have more than doubled in price from 9,000 rupiah ($0.53) to 19,000 rupiah for a pack of 50. "Everyone rushed to stockpile once the prices went up, but small businesses like mine could only buy so much," she told Nikkei Asia, adding that the sheets are also becoming scarcer. Tresnayati is one of the millions of small food vendors in Southeast Asia facing this challenge. Spikes in the price of ingredients, fuel, and, not least, packaging are eating into their thin margins. Few feel able to raise prices. And the recently announced ceasefire between the U.S. and Iran is unlikely to provide imminent relief, according to analysts. On the Dalian Commodity Exchange, the price of a metric ton of polyethylene -- a plastic commonly used for bags, water bottles, and ...