Yes, it's inside his emulator this is how you can get the bios clone of nocash.
Download the emulator from his main site, I don't know if I can post the link here anyway here https://problemkaputt.de/psx.htm
(you can check the legitimacy of the link from gametechwiki No$ page)
You should download the debug version (720 Kbytes) not the gamer version because he cut the debugging feature there.
Open no$psx v2.0 - Utility tab - Remote Access - Create nocash bios rom as raw image (PSX-XBOO.ROM)
Then it will produce the psx-xboo.rom bios inside the folder where the no$psx emulator resides.
I want to upload the psx-xboo.rom bios (256.00k) here but I can't attach the file.
So I upload it via datafilehost here https://www.datafilehost.com/d/56d2cb4d
edit: put the attachment to datafilehost