How to get the update for Galaxy S3;
Install Vpn 1 Click, or any other VPN software.
Then connect to Internet (WIFI or Mobile data)
Run the VPN software and select a server from USA.
It will connect in few seconds.
Go to software update in settings and update.
Now you are done.
Also if you need to get Google Play USA. (Software which is not available in your country)
Log out from Google Play account. (Remove account in Settings)
Run the VPN software as above.
Open Google play and log in with existing account.
You are there.
(Before open the Google play, always open VPN software, otherwise it will automatically open for your country/area
Thanks