A nice cool draft through the window sure helps. You could get some of those blinds that are designed to block sunlight. That will help a little. There is insulation too. If you insulate the walls better you will keep in more of the cold air you have with the ac or fans, whatever you use.
Also, with ac you don't release the freon into the air unless its being recharged, charged, or if there is some sorta leak. So with a new AC that uses freon that should not be an issue.
There is also air conditioners with puron and not freeon. Those would be a way to eliminate the freeon stuff all together.
I recommend getting a window unit if you want to only cool one room. You will need to seal up where it fits in the window real good though.
The Haier ESAD4066 is a very good unit. It uses r-410a, which is puron. It has an eer rating of 12 which is extremely high. You cannot get much more efficient then that. Plus, this unit will also clean the air too. You can order that unit online if you cannot find it locally. They will ship to your country if you request to have it shipped via fedex.