So I may have to forego the 400 and settle for a Raspberry Pi 4 bare metal, and use a USB keyboard. The online sources run $140-180 according to DDG.
What do you think of these?
10 Alternative Raspberry Pi Operating Systems
Raspian XP might be familiar, NAS, boot to Basic, Amigaberry, the original gangster RISC OS, Chromium [not], RetroPi for a gaming platform, Windows 10 [not]. There are a lot of alternatives.