File:Star Wars and the Power of Costume July 2018 33 (Chancellor Palpatine's Senate robes from Episode III).jpg - Wikimedia Commons
I've seen a lot of posts about Palpatine's red sith robe but what about his main prequel skin that he had in both the clone wars and revenge of the Sith :
Palpatine/Sidious (Ep. III red robe) by SithEmperorCharizard on DeviantArt
The tunic, velvet red of Palpatine (Ian McDiarmid) in Star Wars III : revenge of The Sith | Spotern
Hasbro Star Wars Galactic Heroes EMPEROR PALPATINE figure in red Sith robes | eBay