MEMPHIS, Tenn. - The flophouse bathtub James Earl Ray stood in to shoot the Rev. Dr. Martin Luther King Jr. has been sold to an online casino for $7,600, the tub’s owner said Thursday. The auction on eBay began March 20 and ended Thursday afternoon with Golden Palace Casino placing the winning bid, said D’Army Bailey, a Memphis judge who owned the tub. Golden Palace has bought numerous historical or noteworthy artifacts for a traveling display. Its Web site on Thursday touted its purchase of four toilets formerly owned by late Grateful Dead musician Jerry Garcia.