Buy Japanese PSN credit from retailers like Play-Asia .
Search for "Sengoku Basara 4" or "Sumeragi" on the Japanese store to download it directly. 2. Physical Import Sengoku Basara 4 PS3 Free Download
If you're looking to play today, here are your best options for obtaining the game: 1. The Digital Route (PlayStation Store) Buy Japanese PSN credit from retailers like Play-Asia