How about a website header with a link to a static zip that contains the whole website in one hit. The Zip could be hosted on some big public sever. Perhaps even mirrored locally for each nation.
that's hard to do with rendered content, oftentimes the result depends on a backend service. Maybe you should make the service it's running public but that might be a line most aren't willing to cross.
I was thinking you scrape your own website every day in the middle of the night when traffic is low, and make that available. They can come and collect it every day if they want to.