Canada

If you're okay with older homelab-esque equipment, the ERA, also on eBay as Calgary Computer Wholesale, often has really cheap rack mount stuff. This being said, the ERA is a pretty sketchy organization overall (it's closer to a small e-waste recycling business that takes advantage of its status to reduce liable taxes (with variable employee salaries equivalent to dividends) and take advantage of free volunteer labour, than an actual non-profit organization). Sometimes, provincial government surplus auction sites have rack mount equipment as well.

This may not be a popular position, but stay with me: most companies don't need big servers.

I've been working in this industry for 25 years, and in my experience, nearly every company I've worked with could have hosted all of their internal and external services on consumer hardware and even a cluster of low-power devices like the Raspberry Pi.

The real limiter isn't hardware, but network access. You can have a massive k8s cluster in your office, but if your network provider flakes out, your business goes away.

So, I would argue that what we really need is colocated network hubs all over the world capable of hosting cheap hardware. Mythic Beasts here in the UK does stuff like this for example, to get effect.