Not a costume, but an original victorian dress [link] and headdress [link]
To answer to who, looking at this picture, claimed that historical dresses should not be worn, I would like to clarify that... I agree. I have more that 1200 antique clothing items, including almost 200 complete dresses from 1780 to 1930. They are stored flat, in acid free paper, away from light, dust and insects. I never wear them, I collect them only for their historical value. But for one time I wanted to try the thrill. To prevent damages I wore it inside (no direct sunlight), with a T-shirt underneath so it didn't touch my body skin, and for no more than 15 minutes. And I choose a dress my size so it wasn't stressed by stretching.