@ActionRetro C3's are hard to come by...

You may be able to find some #C7-based #industrial and #embedded boards, similar to the SBCs that @rasteri used for the #Wee86 (A #PC104-based Retro Mini PC) and #WeeCee (same concept but smaller and eith a more modern CPU) but those will be frightingly expensive.

Not shure how well #VIA made cross-generation compatibility but consider getting a #ViaNano and see if you can choke it down in the UEFI/BIOS to match C3 performance...