Get T-mobile you get free text and data internationally and $0.20 a min per call. 
If you have time before you go, sign up for bing rewards, and search to get points. you need 300 bing points to get a month of Skype Unlimited US & Canada calling so that can handle your unlimited calling you can get 15 points a day so you need 20 days of searching for the 300 points. It takes about a min and a half to get the 15 points per day.
If you have time before you go, sign up for bing rewards, and search to get points. you need 300 bing points to get a month of Skype Unlimited US & Canada calling so that can handle your unlimited calling you can get 15 points a day so you need 20 days of searching for the 300 points. It takes about a min and a half to get the 15 points per day.