If anyone needs a spare key ,it may come as a surprise that raleigh cannot supply them.
I only have one key for my raleigh Dover and raleigh say they cannot supply new keys. the only thing you can do is buy a new lock for £30 +.
These are identical to the locks on the Kalkhoffs, both models are made by Derby Cycles. You could therefore check with 50cycles to see if their policy is different, or if it's a Derby Cycles policy.