Dario,
Not sure if you have ordered medications yet...
To answer your questions - It is legal to buy medications from a U.S. website, as long as they ship from U.K to U.K.
On Viamedic's website, you can order interational here:
Viamedic.com – Country Information Page
The prices might be a little higher than the U.S., but you will get the real pills.
Hope this helps,
Frank