They're common here in Southern California. Lot's of liquor stores sell them. The one that I buy them from in Huntington Beach charges me only 59¢ each for them. When I first asked the lady behind the counter if they were good out of the country, she said everywhere. I said even the Czech Republic? She said no problem. I sent it to Filip and she was right, he had no problem. She told me that most of the money orders that she sold were sent to Mexico or some of the Central American countries aside from being used locally instead of a personal check. She was tripping when I told her Czech Republic. I let her know she was right after Filip got the money order cashed.
It seems the United States has some of the most liberal banking and money rules around, though I'm not familiar with how other places do it and am just speculating from how most of the questions that people have are from people in different countries.