Download: https://the-eye.eu/public/MSDN/
Checksums (sha1 hashes): https://heidoc.net/php/myvsdump.php
You can use total commander or nirsoft hashmyfiles (my favorite) or any other software for verification.
Files are made by microsoft, and untouched, includes operating systems with latest service packs integrated.
Best to use download accelerators/managers like fdm or idm, and multiple connections at a time (at least 4) to speed up.
Links are resumable and fast (no restrictions).