* Move to sell Real not linked to new investor in Metro -CEO (Adds HSBC analyst upgrade): BERLIN (Reuters) - German retailer Metro AG plans to sell its struggling Real hypermarkets and is confident of interest in the chain, though bankers played down talk it might attract Amazon and a price tag of up to 1 billion euros ($1.2 billion). Industry bankers contacted by Reuters said private equity firms were the most likely bidders and that Metro might have to effectively pay a buyer to take the chain off its hands.