Iron Out 7.6-oz Rust Remover in the Rust Removers department at Lowes.com
Whink 16 Oz. Rust Stain Remover - Clark Devon Hardware
Ring King Toilet Ring Remover, NatureTek Toilet Bowl Cleaner, Multi-Surface Calcium, Water Scale, Rust, Red clay, and Lime stain remover, Fast Acting No Scrubbing 32 Fl Oz (Pack of 1)
How to clean a toilet with CLR Calcium, Lime & Rust Remover & CLR Bath & Kitchen Cleaner - YouTube