I finally explored the hard drives of my Tecra 520 CDT and Satellite 230 CX (I still have the laptops disassembled, but I bought a USB adapter to connect hard drives).
I searched for .bmp, .png, .jpg and .jpeg.
Looks like the original owner of the Tecra 520CDT updated Windows 95 to 98, I found the same wallpapers that are present in the recovery CD, but nothing more.
The Satellite 230CX doesn't have anything related to Toshiba. I think the previous owner formatted the hard drive, wiping all the computer original files, and installed Windows 2000.
I've also made an image of the boot diskette that came with the Tecra 520 CDT (it's not an original diskette, and an error occurred while trying to read the file IO.SYS in the diskette), I'm uploading it here and I hope it can help someone. It was the first time I've used ddrescue, I don't know if I've done something wrong, so I've also included the ddrescue map files and output.
EDIT: Link in VOGONS Drivers: http://vogonsdrivers.com/getfile.php?fileid=1462&menustate=0