On the 1st of October 2007, the laws regarding airsoft guns changed This is a brief summary of those changes, more information can be found here: www.ukara.org.uk If you are under 18 years of age, it is illegal for you to buy an airsoft gun. It is also illegal for anyone to sell one to you, whether you are a skirmisher or not.
Over 18s have to prove that they are airsoft skirmishers. They can do this by taking out membership of an airsoft site which holds third-party liability insurance. In order to facilitate remote selling, UKARA the retailers organisation, has set up a database to which sites can submit their members details. Once a player is verified & on the database, any UKARA member can quickly check that a purchaser is entitled to buy an airsoft gun.
Other Defences may be used against the VCRA, such as Historical Re-enactment, use in Museums, or TV/Film/Theatre production, but this would have to be evidenced and relevant to the RIF's purchased.