Based on this product's specifications, here are some alternatives and similar models
Power Supply No name AK-PD-31 for SONY PSP 1000, 5V 2A 10W
Summary description:
AC/DC power supply No name AK-PD-31 designed for SONY PSP 1000. Outputs 5V at 2A (10W) to charge and power the handheld console. Provides stable voltage for charging PSP battery and running the device during stationary use. Suitable as a replacement adapter for home or travel use where original PSU is unavailable.