Hi Andrew,
Yes you would do this by restricting ship.
1. Go to Setup > Site Builder > Setup Tasks > Set Up Web Site (Administrator).
2. Click Edit next to the website you want to modify.
3. On the Shopping subtab, in the Shipping Page section, clear the Web Store Ships to all countries box.
4. In the Countries Web Store Ships To field, select the countries your customers should be allowed to select at Checkout in the web store.
5. Click Save.