(Reuters) – Many customers will have to wait three to four weeks to get their hands on Apple Incs larger screen iPhone 6 Plus after pre-orders for Sept. 19 delivery were booked out within hours. The smaller 4.7-inch iPhone 6 is still available for delivery on Sept. 19, Apples website showed. (http://bit.ly/1qNAOLK) Apples iPhone 6 Plus, which has a 5.5-inch display, goes on sale in U.S. stores on Sept. 19. Websites of Apples carrier partners, Verizon Wireless , ATT and Sprint Corp , also showed delays of up to six weeks. …