Jetoy choo choo is a South Korean design company whose main topic is cats in a lovely kind of vintage art style, they have a bunch of things like postcards, pens, notebooks, bags, pencil cases, etc...
Jetoy postcards are quite popular along postcard collectors (and cat lovers).
Their webpage is here: http://www.jetoy.co.kr/
(It's in korean but they have an english part to shop)
Dank je Rianne!