This gray, blue, and white outfit was used by Organa nobles during the time of the Alderaan civil war in Star Wars: The Old Republic. It was worn by Elric Organa and available to player characters as the “Organa Statesman” armor.
Jedipedia has excellent 3D turn-arounds of this outfit. Screenshots of the PC armor from Swtorista.
Note: Because Elric Organa is a traitor to house Organa, aligned with the Sith Empire, his specific costume would not be eligible for Rebel Legion membership, but a generic version of this costume would.