Here is what I have been able to find online... FOR YOUR VIEWING PLEASURE!!!
..:: MS-DOS 3.30 OEM Adaptation Kit Source Code.7z
..:: MS-DOS 6.0 Source Code.7z
..:: Windows 2000 Source Code.
..:: Windows XP SP1 and 2K3 Source Codes.
..:: Windows 10 Shared Source Kit.7z
..:: Windows NT 3.5 Source Code.7z
..:: Windows NT 4.0 Source Code.7z
..:: Windows CE 3 Platform Builder Source Code.7z
..:: Windows Embedded 7.2014M12.7z
..:: Windows Embedded CE 6 r3.170331.7z
..:: Windows Embedded Compact 2013 2015M09.7z