Get on alibaba.com, and find a supplier. Most allow customization of the boards you purchase. And the above-mentioned chipsets have full Linux support. Getting arm-based boards with 4+ 10gigE ports is easier than you'd think.

The desktops are all arm-based thin clients running X servers with all apps hosted remotely. If a device fails, plug in another one and keep working.

Richard Stallman abandoned Five Eyes-based chipsets for the same reason, long before I ever did. We should look to him more for inspiration on how to remain free during these draconian times.