Arsenal

Image from ebay store: VIP Fan Auctions

Bow
The only weapon used by Lara in the film, she picks it up after being stranded on the island of Yamatai in the Devil's Triangle.

H&K Pistol
This pistol is not used by Lara and are only seen in a scene before the credits, where Lara admires them and decides to purchase two of them. They are presumably put in as a nod to the Tomb Raider films starring Angelina Jolie.