An article with rusty metal textures was missing from this site which offers resources for designers. There are 47 of them and I hope you haven’t seen them anywhere else so they can be that very thing that you are looking for. You can download these high res textures for free but make sure you read their licenses before using them and respect the authors who made them.
Rusty Violet Texture
Red bubbled metal texture
Rust Texture
Eroded rusted texture
Rusty wall texture 03
Eroded rusted texture 2
Rusty metal
Cold as steel 3 (Forgery)
Grunge Texture 01
Grunge Metal 1
Bright Rust Texture Pack
Fill me up babe…
Abstract Fire Storm Texture
Metal Collage 2
Rusty – texture
Rust
Metal Rust Texture 22
Rusty concrete texture
Metal Bolt Texture
To corrode
Rusty days
Old Metal (3)
Metal Rust Texture 21
Old Metal (2)
Texture Set III Rusty Metal
Metal texture 2
Rusty Screwed Texture 02
Textures 2
Package – Metal – 4
Rusty Texture
Texture Set – Rusty Metal
Oxidized balcony to the ocean 2
Rusty tin texture
Rusty
Rust texture 6
Metal
Peeling Paint Pattern Texture
Rusted metal cable
Nice texture 3
Metal Rust Texture 05
Package – Misc Textures – 2
5 Rotten Rusty Textures Pack 1
Painted rusty Metal texture
Rusty texture 1
Rusty Metal Stock Texture
Rusty Grate Seamless Texture
Nice texture 6
