Accenta Mini G3 KEYPAD?

My Accenta Mini G3 keypad was ripped off the wall by burglars!! I've manged to stop alarm going off but now want to replace keypad, is this easy to do? If I buy a new keypad will it be my same code and how will i stop bell going off while i fix the new one onto wall?
If anyone could help it would be great.

Thanks Ben.