Barrette for 5,000KRW
Simple shimmery golden hairband for 4,000KRW. It comes in other colors as well.
There is a store called Apportion in Korea. Such a strange name for what it sells. It's a hair accessory store. I'm not an accessory girl, but I love hair accessories. Some of their products are overpriced, but I've definitely noticed that their quality is much better than the accessories they sell on the streets.
There are two located in Itaewon. This one above is the bigger one. Just go out of exit 4 and walk straight toward Noksapyeong station.