On the PI server you can find these files @
/usr/sap/<SID>/<instance>/j2ee/cluster/bin/interfaces/keystore_api/lib/private/sap.comtcjekeystore_apiAPI.jar
the other one might be @ /usr/sap/<SID>/<instance>/j2ee/cluster/bin/interfaces/security_api/lib/private/sap.com~tc~je~security_api~impl.jar
Regards,
Hareesh