A platform for a stator vane includes a platform body and a plug. The platform body defines: an inner surface, an outer surface offset from the inner surface, an internal fluid passageway disposed between the outer surface and the inner surface, and a core aperture extending from the outer surface to the internal fluid passageway. The plug 700 is configured to be secured to the platform body. The plug is configured to be partially disposed inside the core aperture and extend outside of the core aperture whilst secured to the platform body for improved heat transfer between a fluid conveyed by the internal fluid passageway and a fluid to which the outer surface is exposed.