Look at the wee X99 board; ASRock's X99E-ITX/ac - PC Perspective
NO MORE EXCUSES - Asrock develops the very first Mini-ITX X99 motherboard - Motherboards - Level1Techs Forums
Found this on Facebook marketplace for $20 with everything that came in the original box except the wifi antenna. Going to try and find parts for it and see it it works.
ASRock X299E-ITX/ac “The Little Monster” detailed – SFF.Network | SFF.Network