Download server for resources (<MC 1.5.2) returns 403 response code (s3.amazonaws.com/MinecraftResources)

It appears that the older versions of minecraft had a different way of downloading the sounds and music. The download link for these resources is returning a HTTP response code 403.
The following is an example from the log added:

[0316/145745:INFO:GameCallbacks.cpp(178)] game/game () info java.io.IOException: Server returned HTTP response code: 403 for URL: http://s3.amazonaws.com/MinecraftResources/sound3/ambient/weather/rain1.ogg

This issue appears to be recent, most likely less than 3 weeks old.

I've tested this in BOTH the native launcher and the legacy java launcher, as well as some often-used third-party launchers. Each return these exact 403 errors.