The first pavilion where I was able to get some cards was Switzerland. They had a big collection of cards and they were free.
The view cards I got shows the Old Mill of Bruzella in the Canton of Ticino, the Crans-Montana in the Canton of Valais, islands in the Urnersee in the Canton of Uri, the Lake Davos and the Val Müstair in the Canton of Graubünden.
I also got some cards showing Swiss food.
At the pavilion there was also the possibility to buy stamps and to send cards from there.