I thought there were only one type of Forever stamp. Seems there is an international stamp. This made my day because postage can be pricey. If you mail a lot of letters like I do, you'll love these stamps too.
The cost is $1.15 per stamp, but well worth it. I bought my first sheet of stamps from the post office using their online portal. Just a heads up, you can buy these stamps from Amazon too. They'll get to you a little faster if you're in a rush to receive them. What I love most is that you can sen up to four pieces of paper and one stamp will cover it.