I finally found it!! It took some searching, but I finally found the website for this "hidden gun case mirror". The company is called Tactical Walls, and they have a lot of different options for stuff like this. This particular set up is only $375!!
The #1 Concealed Carry Tank Top for Women. made in the USA by Undertech Undercover. "Why Carry Your Gun? When You Can Wear It!" CCW, Concealed Carry Holster, Concealed Carry Shirt, Concealed Carry Clothing