"Buy now" buttons and online shopping carts are not generally how organizations looking to spend serious money on AI buy their hardware.
They have a long list of server hardware partners, and odds are you'd already have an existing relationship with one or more of them, and they'd provide a quote.
They even go one step further and show off some of their partners' solutions:
https://www.amd.com/en/graphics/servers-instinct-deep-learni...
FWIW I believe Supermicro and Exxact actually do have web-based shopping carts these days, so maybe you could skip the quotation and buy directly if you were so motivated? Seems kind of weird at this price point.