The easiest way it purchase 1.3 and 3.1 is exactly how Transition as alluded to:
Step 1 buy Amiga Forever,
Step 2 buy a Catweasel Mk4 or Mk4+.........
In my opinion if you are a classic amiga user the Catweasel (on a PC) is worth every penny.
Would you really what or need any of these version of amiga OS: 1.0, 1.1, or 1.2 1.4, 2.0, 2.04, or 2.1?. I can maybe see wanting a version 1.0 or 1.2 roms to boot some old games but probably not the OS
As for 3.5, 3.9, and 3.9withBB2
Unless you are in a special situation, with a 68020 one would probably not want os 3.5
or 3.9
just OS 3.9with bb2 and is that not still available?
As for a HDF file, one can use WInUAE/Amiga Forever to make any HDF file they wish, out of the Amiga Forever's files.adf and/or AmigaOS Cdroms.
@hceline, I don't remember signing any CUDA saying that I can only use the .ADF files with an emulated amiga. This sounds more like a distribution agreement Amiga Forever made with Amiga, Inc.
Anyway, don't just about all of use have at least original copies of amiga os 1.3 and 3.1 and maybe 3.5 and 3.9?