Sometimes, if you have a legitimate reason, contacting Apple Support directly might help you access what you're looking for.
I notice you’re asking for a of a “macOS High Sierra 10.13.5 image file” with a reference to -.rdr- (which looks like a typo or placeholder — perhaps you meant .dmg , .iso , or .cdr ?). download macos high sierra 10.13.5 image file -.rdr-