Vishay # Si2301DS is obsolete and has been replaced with Vishay # SI2301CDS.
SI2301CDS
Vishay Siliconix
MOSFET P-CH 20V 3.1A SOT23-3
Datasheet - SI2301DS SI2301BDS
Datasheet - SI2301CDS
Please review the datasheet to ensure the alternative will work for your application.