The only strictly legal way to obtain these files is to "dump" them from your own physical PlayStation 2 console using homebrew software like FMBC (Free McBoot) .
Distributing BIOS files publicly is illegal because they are copyrighted software owned by Sony. Users are encouraged to obtain them through legal methods: all ps2 bios files including the new scph90006 hot
For reference, below is the exhaustive list of distinct PS2 BIOS releases (excluding minor regional variants): The only strictly legal way to obtain these
The most refined versions, typically extracted from late-model Slims like the SCPH-70000 and 9000x series. These offer the best stability for modern emulators like PCSX2. Legal and Practical Setup all ps2 bios files including the new scph90006 hot