307cc boot locked?

Hi, I have broken the remote locking fob for my 2004 307 cc. The lock button still works, but the unlock button doesn't. I've been to my local dealership, who want £148 for a new fob (car is probably only worth about £600, so that's really not an option!). I can lock & unlock the car with the key, but am unable to get into my boot. The '0' on the 307 just feels as if the car is locked and cannot be depressed at all. Have got things in the boot which I can't get out and will not be able to use the roof as the screen is not in place. Any ideas would be greatly appreciated.