Hi,
No web-adress as far as I know but you can try them at:
+49 725571240 (don't know if the number is still valid).
Oh, and Safety Devices makes a weld-in cage for the 1302 but this probably will fit a 12/1300 body as well.
http://www.safetydevices.co.uk/oldsite/carcages.htm
Good luck,
Cheers,
Richard