Anyone knows where to buy a cargo chest for pick up?

Hi. Does anyone know where to find a box that is placed on the cargo bed of a Ford Ranger? I don't know what it is officially called. On the internet it can be found under the name tonneau, some calls it toolbox, for me it's like a chest. I think the Mitsubishi Strada has a built in one on their new models.
Are there lots of this in Banaue? Does anyone know how much they cost? Thanks.