Caribou Coffee Co. will close two of its Chicago locations on Sunday and convert the remaining 14 to Peet's Coffee & Tea in the next 18 months. The move is part of a broader restructuring plan that calls for the closing of 80 nationally underperforming stores and the revamping of another 88. Caribou stores at 2453 N. Clark St. and 500 W. Madison St. are slated to close, according to the Brooklyn Center, Minn.-based customer service line. The moves come months after Caribou was purchased by Joh. A. Benckiser Group GmbH of Germany for $340 million.