While the standard consumer ISO is gone, certain specialized versions may still have active landing pages:
Microsoft removed the official tool link, but the tool itself still works. Download the MediaCreationTool.exe for Windows 8.1 from a reputable tech source (like the Internet Archive or Microsoft’s old TechNet library). Run the tool, select "Create installation media for another PC," and choose your language, edition, and architecture. The tool will download the ISO file directly from Microsoft’s Akamai CDN. download windows 8.1 disc image -iso file- - microsoft
Burn to DVD: