To change the country code in Google Play can be a real hassle because it's not clear how it works and even when you live in the 'right' country for a while, Google sticks to your old country, as long as you don't qualify for the new country (probably with a payment method from the new country).
Therefore open a browser window in incognito mode (like in Chrome) and goto Google Play. There search for the app and click on install. Then you will be asked to log in and you can do this and the app won't disappear !!! ;-)
Good luck and have fun !!!