Now open at the Viceroy Anguilla and at the Copacabana Palace in Rio de Janeiro (see our City Style guide to Rio here), Seaside Luxe’s newest resort-based boutiques are bringing the company’s well-sourced apparel, jewelry, and home goods outside the United States for the first time. (The Santa Monica, Calif.–based retailer’s shops at the Four Seasons Hualalai and the Four Seasons Maui opened in 2009 and 2011, respectively.) Seaside Luxe not only offers a site-specific mix of athletic, resort, and more formal a…