Raymond James is nearing an agreement to buy Region’s Morgan Keegan brokerage unit for about $930 million in cash. Raymond James may tap Morgan Keegan Chief Executive Officer John Carson as its president and head of fixed income according to news reports. Adding Morgan Keegan would bring Raymond James one of the top underwriters of U.S. municipal bonds and would expand its retail brokerage network, placing it among the nation’s biggest firms. Raymond James has about 5,100 financial advisers compared with 1,200 at Morgan Keegan. Regions plans to collect a $250 million dividend from Morgan Keegan before the sale, boosting the amount of cash proceeds to about $1.2 billion.