[OFFER] Various missing Windows NT builds and service packs
There is only one known build of Cairo.
Seems to be more here: http://mirror.macintosharchive.org/max1zzz.co.uk/+Windows & DOS/Windows/+System/Windows NT 4.0/[Beta]/Cairo/
NT 3.1 SP1 and SP2: https://mega.nz/#F!OpdiWCwB!UOfcbT24P4LZEPXzm9jm-w
NT 3.51 SP5 for Alpha: http://ftpmirror.your.org/pub/misc/ftp.microsoft.com/Softlib/MSLFILES/SP5_351A.EXE
NT 3.51 SP5 for MIPS: http://ftpmirror.your.org/pub/misc/ftp.microsoft.com/Softlib/MSLFILES/SP5_351M.EXE
NT 3.51 SP5 for PPC: http://ftpmirror.your.org/pub/misc/ftp.microsoft.com/Softlib/MSLFILES/SP5_351P.EXE