Hi,

With the help from Esri I was able to download the existing PictureMarkerSymbols that are available from their website, as shown here

http://developers.arcgis.com/en/javascript/samples/portal_symbols/index.html

You can download the ‘zip’ (tar.gz) with all symbols from this location

http://bjorn.kuiper.nu/upload/blog/symbols.tar.gz

Enjoy!