Borrow a friend’s PS1, use a PS2 with FreeMcBoot, or buy a cheap “for parts” PS1 on eBay. Dumping your own BIOS takes 10 minutes and keeps your retro gaming hobby 100% legal.
The BIOS (Basic Input/Output System) is the low-level firmware that Sony originally installed on every PlayStation. It handles the famous startup logo and, more importantly, provides the instructions games need to talk to the hardware.
This is the 100% legal method because you are creating a backup of hardware you already own.