Allow me to say I'm sorry to those of you who posted very encouraging things and never received a response from me! I am very grateful for all of your interest. Forgive my delay to responding to your comments, I have been away from the site for a few months but I will do my best to answer the questions you've asked me!
First: This costume is actually NOT in the Game of Thrones show itself. This was a fusion of King Varian Wrynn's armor from World of Warcraft (design wise) put in the context of House Stark from Game of Thrones.
Second: The "shiny" shirt underneath was actually a crudely sewn together shirt, using a sparkle/sequin, gold fabric from JoAnn's Craft store. It did a nice job adding more shine to an already shining armor. Next time I'll try to avoid sequins, but they do reflect light well.
I have been busy designing my current project, which will be substantially more difficult. If you're familiar with the character Imperius, Archangel of Valor from the game Diablo III, that is the goal. I have seen a few other great Imperius costumes out there already, and they do inspire me to keep working. If I have my way, it will include lights and large wings. I'll start another WIP thread when I have more to show. Thanks again!