I found this lot of seven Thinkcentre m710e SFF with Core i5 7th gen on ebay… a first step to start building my own on-prem k8s cluster :) : r/thinkpad
Lenovo ThinkCentre M710e Intel® Core™ i3 di settima generazione i3-7100 4 GB DDR4-SDRAM 256 GB SSD SFF Nero PC Windows 10 Pro
Lenovo 180W Power Supply for M710E | Laptech The IT Store.
LENOVO THINKCENTRE M710E Intel Core i3-7100 8 GB RAM 256 GB SSD PC Windows 10 Pro EUR 87,82 - PicClick IT