For Korean fashion accessories in Singapore, you can visit Shine Baby, which has one location available, operating within HarbourFront Centre (1 Maritime Square). (UPDATE 2022: THE STORE HAS CLOSED)
The shop retails a wide range of fashion accessories that have been directly imported from South Korea.
These fashion accessories include, for example, rings, earrings, as well as necklaces.
Shine Baby HarbourFront Centre – Korean Fashion Accessories in Singapore (UPDATE 2022: THE STORE HAS CLOSED)
1 Maritime Square, #01-74, HarbourFront Centre
Other similar costume jewellery stores you can find within the same building complex include, for example Mixshop (#02-95).