Henry,
My 2010 +4 Duratec has given me key problems with the immobiliser module dropping out making the car unusable.
The local specialist key guy programmed the keys for me but had to order in a key which had enough 'meat' on the plastic end to allow it to be drilled out and have an immobiliser module inserted. It's a bit like a 1" long matchstick.
They will need the car and all the keys as they will all need programming again to the same code.
The key Co I used is in Aylesbury and charged £80.00 for a new key plus reprogramming and they did get in a stock of key blanks some 18 months ago
Whilst you are at this key business check that the modules are fixed into all the keys with adhesive - all mine dropped out at some stage .
