A lack of outstanding specialty apparel retailing talent may force Gap Inc to look outside the sector for a successor to CEO Millard "Mickey" Drexler who last month announced he would step down after 19 years at the helm of the casual clothing giant. Gap Inc, which also includes Old Navy and Banana Republic in its portfolio of stores, has taken the unusual step of hiring two executive search firms to find Drexler's replacement: Heidrick & Struggles International Inc and Herbert Mines Associates.