radio code, plz help

[harvin]

Hello, am new here, i dont know if this is how its done but my radio is asking me for a code of which i dont have, and i dont have money for a new 1 from the local dealer please any 1 help me get a code for a 2005 Nissan pulsar radio
B8185-6M902
Model code 14787211
Serial Number 0040971

Thanks in advance.
any 1 plz help me :(