Did you try to make your own mirror for wheezy?
It is about 100 GB.
No, I haven't tried that. Do you mean as a temporary step to allow the ISO build process to work, or as a permanent step for the ISO installs to update from?
All I am really trying to do is create an exact copy of the existing ISO with the /etc/apt/sources.list pointing at the archive server rather than at a non-existent URL.
is it possible to just edit a file inside a .iso image? I imagine it isn't trivial as everything is zipped up.
"A motorcycle is a bicycle with a pandemonium attachment and is designed for the especial use of mechanical geniuses, daredevils and lunatics."
— George Fitch, Atlanta Constitution Newspaper, 1916