AFAIK Microsoft have not, and will not be publishing a separate installation pack for the media pack under 2004, or any later windows versions.
As per earlier posts in the thread and in some of the less easily found Microsoft declarations.
(Microsoft staff seem to be getting better at obfuscation.)
The facility is included in all the new windows variants as a OPTIONAL facility
so - when you get windows 2004, N or other variants, the feature code is included - and (possibly with just some variants) the USER has to post-install, go and tell the windows feature installing process to install that feature.
The user will then need to get and install any of the optional codec's - those being accessible as detailed for the earlier version of windows.