â A new cooperative promises to help small, independent subprime lenders maximize their revenues, lower their expenses and boost their market shares. The cooperative, known as Patriot Lenders, was launched last week in St. Louis by Lenders One Mortgage Cooperative, which bills itself as the largest alliance of prime mortgage originators in the country. Officials said the new nonprime co-op will help lenders “operate more efficiently and profitably by leveraging the power of the…