Here you can download a number of older Scratch images. A large number of these have been leaked from a third-party site no longer available as well as some obscure download links on MIT servers. The October 2004 build is the oldest still available for download directly from MIT servers at https://llk.media.mit.edu/courses/software/scratch/
This version contains a plentiful amount of information, including the October 2004 build, some sample projects in that version, and a large amount of documentation. Five other pre-release versions are available but only in .image files
Available images: