My spouse and I have recently been spending a lot of time in Costa Rica. When we need new quality luggage or have to buy an air mattress because family will be visiting, there's one place we know will have what we need: Pricesmart (Nasdaq: PSMT).

The stock deserves a place on your watchlist because it gives you international exposure while banking on a growing baby-boomer trend.

First, a little history
Originally founded as Price Club in the 1970s, this company was in the wholesale business long before Costco (Nasdaq: COST), BJ's Wholesale (NYSE: BJ) and Wal-Mart's (NYSE: WMT) Sam's Club were even on the scene.

In 1993, the Price family decided to merge their chain with Costco. A year later, Costco spun off their international rights into what is today's Pricesmart. Motley Fool co-founder Tom Gardner has made Costco one of his core holdings on the Stock Advisor service, so the fact that Costco DNA continues to be a part of Pricesmart bodes well for investors.

Today, Pricesmart operates 28 locations in 12 countries throughout Central America and the Caribbean. They also plan on expanding to South America with a location in Columbia this year. Such a move could be the start of expansion into the continent, which could drive growth for years.

A distinct clientele
If Pricesmart members were just like their counterparts in America, you would expect to see many middle- to upper-class local residents joining the club. In reality, the demographics of Caribbean and Central American nations are vastly different than in the U.S. Only the truly wealthy find it beneficial to pay for membership. In addition, the price of goods isn't normally what attracts buyers to the store; taxes on imports usually make Pricemart's offerings more expensive than if they were bought in the states.

What, then, is the draw for customers? It's simply that Pricesmart is the only place where customers can find certain products that are normally available in America. This, therefore, leaves North American ex-patriots -- particularly baby boomers retiring to a warmer climate -- as the demographic to focus on for continued growth.

According to CBS' MoneyWatch, a bit more than 500,000 retirees currently live abroad. With 79.6 million baby boomers looking to retire in the coming years, that number will increase dramatically. Central American and Caribbean nations offer affordable health care and living expenses compared with the United States. If you consider the fact that nearly half of the baby boomers haven't saved up enough to live stateside and maintain their standard of living, you've got an undeniable trend on the horizon. When these people need the goods they're used to but can't find them at the corner store, they'll be heading to Pricesmart.

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