High Finance: Three for a Pyramid

HIGH FINANCE One is a former junkman who began entrepreneuring at 16 by buying a deserted jail and selling its steel bars at a profit. Another is a courtly Southern tycoon who lives in a mansion in Yemassee, S.C. The third man once conducted his family business, the nation's biggest maker of toothpaste tubes, from a floating desk in the pool of his Greenwich, Conn., home until the pool became too small to contain his world. They make an unlikely trio, but together they have set out to be corporate conquerors in the style of Louis Wolfson and the late Robert Young. Last week the trio completed a major coup by taking control of ailing Lionel Corp. from Attorney Roy Cohn, bumping him down to chairman of the executive committee. That coup expands the assets of their growing empire to $140 million.