Peugeot 307 SW - Front passenger door locked - yoyo

The front door of my Peugeot is locked (other doors and boot can be opened). Have taken it to the garage but they are unable to remove the door card without cutting through it. A new one will cost £378 and the cost of repairing if problem is as suspected will be £208. Anyone know how to get this off without needing to replace it? Am changing car soon so reluctant to pay this amount. Currently trawling web for breakers to see if I can find one with no joy as yet.