Girls’ Generation stamps that have started going on sale on August 9th were half-sold in only one hour! That’s right, they were that popular. In the photo below, you can see that the queue was really long.
For SONEs who are unfortunately not Korean, don’t worry, the stamps can also be found for pre-order on YesAsia here. They’re quite expensive (to me anyway), for around US$10.85 (depending on your country) but at least shipping it free!