Reddit reviews Weegee: Murder is My Business

You could try Richard Goodall Gallery for music/movie posters, not sure how many metal bands they have...if any. Also I'm not sure if anyone sells prints of Weegee's photographs but he is famous for arriving on crime scenes before the police to grab his shots, here are some examples and here's a decent looking book. There's also this book that I've been trying to track down a copy of in the UK, Smoke Gets In Your Eyes about working in a mortuary.

If he's into vinyl, a lot of metal bands put out limited edition releases which you can probably get for somewhere around £30-50 or even if he's an Argento fan, the Goblin soundtrack to Suspiria would be pretty cool

Fright Rags and Rotten Cotton do horror T-shirts and Rotten Cotton even has an Italian-Horror section with a few Argento items

I have this book, but I don't think I've ever seen that taxi picture before. It's freaking DEMOLISHED, did it get hit by a train?