Gentlemen:
Perhaps you may find this ammo interesting. It is an original, sealed box of DWM 7.63 Mauser ammo from around the beginning of the last century.
The patronen number 403 was also used by BKIW/DWM for its Borchardt ammo, and, as Ron Wood noted in a previous post, both C96 and C93 ammo appear to have used the same bullet number 203.
Regards,
Gene