Here ist List with the spare partys of the DL380e Gen8 Server (official HPE Webside):
https://support.hpe.com/hpsc/doc/public/display?docId=emr_na-c03366122
If you are using v2 Processors, the SB you have will not be able to boot up. You need this one:
System board assembly - for Intel Xeon E5-2400 and E5-2400 v2 processors, Ivy Bridge
732151-001