The temples in Asakusa should be visited regardless of the game reference, especially at night! The place can be packed with tourists, especially during the Buddha’s birthday (Hana Matsuri) in Spring.
The temple is a great place to visit at night, after the tourists have gone, as you can get some better photos and the lighting is atmospheric. On the other hand, during the day, the path leading up to the temple is filled with tourist shops with all kinds of souvenirs. The surrounding streets contain hotels and restaurants but after 10pm it gets quiet really fast.
If you’re looking for a Tengu mask, I would recommend the higher quality ones which you can find on the path leading to the temple for around 7000 yen. Not cheap, but solid, yet should not be packed in the suitcase, rather, carried by hand.