If you already bought DLC, you can still redownload it through your "Purchase History" or "Download List" on the PS3. Understanding ".PKG" Files

Most custom content originates in PC format on community indexing sites like CustomsForge . To bring these tracks over to the PS3 console: Go to product viewer dialog for this item. Rocksmith 2014 Edition (Game Only) - (PS3) PlayStation 3

Compressed archive files used inside the game directory to hold individual song assets. Accessible via file managers on modified consoles. Best Practices for Game Preservation and Stability

Official DLC PKG files require a corresponding .rap file (an activation license) placed in the exdata folder of your USB drive or internal hard drive to unlock the content. Step-by-Step Installation Process