Out here in the hot dry southwest we have evaporative coolers or "swamp" coolers. They are basically a box with a blower in it. The sides have panels that hold aspen shavings(or foam etc..) water trickles down through the panels soaking the pads. The blower pulls the air through the pads and the process of evaporation cools the air.
Anyway they are pretty common here, sounds like not so common where you are. I am sure if it will do what you are looking for but if it is you could order one. A small window one is around $250.00 us