The upcoming 1.2.1 version of the AMP plugin allows you to export and download Stories as a ZIP archive.
This archive contains the HTML as well as all the assets for a story and allows you to host the generated story on another server.
You can find the new export functionality via the “More tools & options” menu in the upper corner of the editor:
Simply click on “Export Story” and a ZIP file will be generated for you.
The base URL of all the assets and links within the story can be changed in the plugin settings: