£5 delivered sounds good. PM me your paypal details and I will send you the money.
And don't worry about a trapdoor. I already have one spare from the system the case is needed for. The A1200's current case looks like it was dropped by the previous owner as there is a whole section of the left-hand side missing and the top is cracked from the left across the top of the keyboard. The actual system surprisingly works perfectly though.