I am afraid that what you are asking isn't possible, as when the SIMs are sent they are not activated and can only be activated when connected to the UK home network, the way around this is for the SIM to be sent to a friend or family member to allow them to place SIM in phone to activate it and then forward too yourself.
I'm a Very Insightful Person, I'm here to share knowledge, I don't work for Virgin Media. Learn more
Have I helped? Click Mark as Helpful Answer or use Kudos to say thanks