Install windows 8.1 and use bypass esu to have server 2012r2 update... ( bypass esu blue.. + wsus proxy )
You can find the 6.3.9780 and 9785 builds on archive . org (if linking to that site is inapproprite, Moderator or Admin is welcome to delete it)
Better use windows 8.0 rtm + delete metro apps and mix windows embedded update ( ie11 + net frameworks 4.8 ) and server 2012 esu update ( update up to 2029 ( for 64 bits ) Or update up to .07.2023 for 32 bits with embedded standard update