The US is pressing ahead with plans to hit six nations that tax Internet-based companies with retaliatory tariffs that could total almost $1 billion annually. Goods entering the U.S. -- ranging from Austrian grand pianos and British merry-go-rounds to Turkish Kilim rugs and Italian anchovies -- could face tariffs of as much as 25% annually, documents published by the U.S. Trade Representative show. The duties are in response to countries that are imposing taxes on technology firms that operate internationally such as Amazon.com Inc. and Facebook Inc.