For quality calipers, Mitutoyo (Japan) is the most commonly seen. Other companies making them include Starrett (USA), Mahr (Germany), Sylvac [Fowler] (Switzerland), TESA Brown and Sharpe (USA), and SPI (Switzerland). Note, though, that the most common sizes from most brands are manufactured in China, although Mitutoyo makes most of their products in Japan.
MSC is a decent place to purchase from, and will tell you country of origin.