Thanks everybody, I sorted it out.
The trick is to select UK as your country in the main page (you can change it in the successive page when you make the payment). I bought it for £ 59.99 ($96).
So what you should do is:
1. Cancel the automatic renewal at least 10 days before the expiry date. (if you don't, they will automatically renew it / charge you a week before it expired !!
2. Go to http://uk.norton.com/, and click "Buy now" for the product you want
3. In the next page, remove / or not the "Norton Virus Removal Assurance", I don't now what it is. Continue
4. "Billing & Payment Information" and you Card details. You are buying the product as a new customer. Enter the same e-mail and password that are associated with your present account. Continue
5. The next page will give you the Product Key. No need to download, as you already have the product in your computer.
6. Right-click the Norton icon in the system tray of your computer, Open Norton
7. In the bottom of the window, it says: XXX days remaining Renew. Click on Renew.
8. Enter your product key you just bought (do not click on "Express Renewal, it will take you the expensive version of the renewal). DONE
If you now log in into your http://wwwmynortonaccount.com, you will now have two products, the one that has expired (or is about to expire), and the one you just bought. (The new one may say "Not activated" if the old subscription has not expired yet)
HTH