Japan's Nikkei 225 Index has been among the top performing foreign stock market indices over the past several months. Over the past three months, the index has jumped more than 35% amid Prime Minister Shinzo Abe's reform plans. So, should investors be buying into the Japanese boom or has much of the enthusiasm already passed?

Japan's stock market has risen largely because of the lower yen valuation, which has helped many of its large exporters post record profits. For instance, Toyota Motors recently reported profits that soared past analyst expectations. Unfortunately, the yen's valuation may begin to level off, as the forex market has priced in a lot of the rhetoric.

The question is now whether long-term structural reforms will be successful. If so, Japan could see a lengthy bull market after decades of stagnation, making the Nikkei and other Japanese investments favorable holds. But until there's more clarity, investors may want to seek out undervalued names, perhaps like Carl Icahn's new target - Sony Corporation (SNE).

Hong Kong is known as the world's freest economy and a leading international financial destination, although its performance has suffered a bit from China's slowdown. The country's benchmark Hang Seng Index has jumped 2.24% so far this year and 20.15% over the past 52-weeks, which has lagged the S&P 500's 16.67% and 26.90% performance, respectively.

However, international investors know that emerging markets in Asia represent a key component of future global growth, making Hong Kong an important investment destination alongside other countries like Singapore. Those looking for exposure may want to check out the iShares MSCI Hong Kong Index ETF (EWH) for their portfolios.

Chinese stocks appear to be priced relatively cheap by historical standards, suggesting that investors may want to transition from real estate to equities, according to a recent article in the Wall Street Journal. While the real estate market may have been a big winner between 2008 and 2012, the country's equity markets took a significant haircut amid investor skepticism.

Chinese families investing in the local Shanghai Composite lost money for the most part - 56% of the time at least, according to the article - with about 22% breaking even. Stocks are now trading at a 27% discount to their historical averages based on price-earnings ratios, while many other countries in the region are trading at steep premiums.

As a result, even international investors may want to take a look at China's stocks.

Canada's economy has shown several signs of improvement over the past few months. In February, economists upgraded their forecasts for the first quarter following greater than expected growth, although the central bank is expected to keep rates steady.

These gains are being driven largely by the potash mining, oil and gas, and manufacturing sectors, which could help boost major indices like the TSX 60 index. U.S. investors looking to build up their exposure may want to check out the iShares S&P/TSX 60 ETF (NYSE: XIU).