What do you do when the company you founded is bought by foreigners for $310 million? If you're Mary Tyler Moore, you keep working. And you make some charities happy. Moore said Wednesday the sale of MTM Entertainment Inc., the production company she co-founded, will free her to boost contributions to the arts and to the fight against diabetes. A diabetic, Moore is international chairman of the Juvenile Diabetes foundation. Just how much money does the 50-year-old get from the sale of the company that bears her initials to Television South PLC of Britain? "Enough so I don't have to learn to type, after all," was all she'd say. Sale or no, Moore is set to appear in a new MTM series slated to make its debut on CBS this fall. The romantic comedy will feature Moore as a divorced mother working for a politician. In the series, she marries a blue-collar worker from New Jersey with children of his own. "These children are going to be real children. They're not going to be cartoon characters. They're not going to be little munchkins with quips."