car radio help ,

[sullly]

hi , looking for a code for a siemens vdo , 330886636, its from a corsa ,
the number on the side is gm020532110645,

new battery fitted , so lost the code

cheers in advance if anyone can help ,

 

[stevemac40]

I thought these could only be gotten from the dealers and cost £20 (or some equally extautionate amount).