Costa Rica: 7

Costa Rica's main trade partners are the US, Netherlands, China, Mexico, Venezuela, and Japan. Their main trade partner for both importa and exports is the US. They used to import a fair amount of things from Japan, such as raw materials, consumer goods, capital equipment, petroleum and construction materials. After what happened in Japan in March, they will no longer be importing these things from Japan, but I'm sure they will find a way to make up for it, but it will take a small toll on them.

Luxembourg: 9

Luxembourg mostly trades with local countries, since they are so small, they don't have much to export and import. Their main trade partners are Germany, France, Belgium, UK, Italy, Netherlands, and China. All of these places are pretty stable partners for trading.  Luxembourg has a very stable economy itself, so other countries can also easily depend on Luxembourg for trading as well.