Signaling an aggressive new strategy to upgrade its collection, the Minneapolis Institute of Arts has paid a record-setting $602,500 for a rare set of 17th-century Japanese armor. Sold by the Idemitsu Museum of Art in Tokyo at an October Christie's auction, the intricate iron and leather suit, with gold lacquer and gold leaf, is "hands down the best to come on the market in at least three decades," said Matthew Welch, the museum's assistant director and curator of Japanese art, who has been looking for such a piece for 20 years.