That depends on who has access through the server configuration and .htaccess . I usually keep a development tree, and never depend on the production side to provide the source.

If I need to repair an installation, I require a baseline of all site files with md5sums to immunize me from blame for things I didn't do.

To provide a source url for a site file, just provide a sub in the admin area to read the file and print it to you with the correct file name and Content-Type.

(Added) Btw, I don't see what this has to do with local drives.

After Compline,
Zaxo