You can find 1607 repacks on archive.org, torrent sites, or private trackers, but using one on a real PC is a bad idea due to security holes. If you must have 1607 for legacy software, get the untouched ISO (via MSDN, or known-good dumps) and manually disable telemetry/services instead of trusting a repack.
Repacks from unofficial sources often contain "clipper" malware that steals cryptocurrency or UEFI hijackers that are nearly impossible to remove because they infect the PC's firmware. Compromised Privacy: windows 10 1607 iso download 64 bit repack
A repack ISO can include a "sneaky" script that: You can find 1607 repacks on archive
against official Microsoft records to ensure it hasn't been tampered with. Hardware Compatibility Compromised Privacy: A repack ISO can include a
: Modified ISOs are essentially images of someone else's customized setup; there is no way to verify if keystroke loggers or unauthorized remote access tools have been pre-installed. Legal Risks