I don't have a copy of the original, but it is possible to have Fallout 1 run on a classic Mac OS PPC system with a little futzing around. Here's how:

Download Fallout for OS X. The Garden link for this is hosted at uploaded.net & if you're not registered they make you wait a very long time to get it, plus try and foist downloaders onto you. Persist and DL the .zip file only. Unregistered, it takes 2+ hrs (what it took for me to DL this just yesterday).

Download the v1.1 Update file linked on the Fallout (for Mac OS 7-9) page.

Create a new empty folder on your OS 9 or earlier PPC Mac, name it Fallout. Extract the 1.1 Update and install it into the new folder. This gives you the classic Fallout 1.1 app you'll need to run the game, it also creates a folder called "Data" in the new Fallout folder.

With the downloaded OS X version of Fallout (Fallout.dmg.zip) you have to access its contents. This can be done either on Mac OS X or a Windows PC. On OS X this is; unzip and mount the .dmg. On Windows, unzip & use the Commandline tool dmg2img.exe to create a .iso from the .dmg which you can burn to CD.
The command line here using dmg2img is: dmg2img -i Fallout.dmg -o Fallout.iso
(dmg2img must be in your PATH & run from within the same directory as Fallout.dmg. Or place a copy of dmg2img.exe into the same directory as the .dmg to convert, using the above command from within the same directory). Once done - use your burner to burn the .iso to CD.

The .iso, should you create one, is also mountable on a classic Mac OS without burning to CD, using the Virtual CD/DVD utility, from here. Tho' it requires Mac OS 9.x to be able to "Show the Package Contents" of the OS X "Fallout.app" file. Also, this .iso or CD, is HFS+ so its content will only be accessible with a Mac OS 8.1 or newer.

Assuming you now have a mounted CD, .dmg or .iso, inside is the OS X "Fallout.app". Right-click or Ctrl-click its icon with the mouse to get a "Show Contents" type menu. Inside the package window open the "Contents", then "Resources" folder, then "GameData" folder. Inside the "GameData" folder, copy "critter.dat" & "master.dat" over into the "Fallout" folder on your classic Mac system. They can reside in the same location as the installed Fallout 1.1 application. Also inside the "GameData" folder is a folder named "SOUND", this folder needs to go inside the "Data" folder of the Fallout folder on your classic Mac OS.

Note 1: Also inside the "Resources" folder is a sound file named "duckandcover.aiff", I'm not sure where this is meant to go, so I placed it into the Data:SOUND folder of Fallout on my Mac OS 9 system. It doesn't seem to be a problem. - No other files located inside the OS X "Fallout.app" are needed for the classic game. [Edit] Have since found reference to "duckandcover.aiff" as belonging to the OS X "Fallout.app" built-in "OmniGroupCrashCatcher". So its probably not required for the classic version of the game at all.

Note 2: Both "critter.dat" & "master.dat" combined are over 500 MBs in file size. If you're pushed for disk space, you can make a CD named "Fallout" and have these two files in the root level of the CD. You can then load the CD when you want to play the game & Fallout 1.1 will find it OK

Note 3: If you want to play Fallout on a Mac OS earlier than 8.1, if you make a CD to hold "critter.dat" & "master.dat", then you have to ensure the CD is HFS formatted & not HFS+

And that's about it. You can now play Fallout v1.1 on a Mac OS 7.5 - 9.2.2 PPC using the above steps as a guide.

I have re-uploaded Fallout (for Mac OS 7-9)