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 is configured to be secured to the platform body. The plug is configured to occupy no less than 50% of the core aperture by volume whilst secured to the platform body to at least partially eliminate recirculation of a fluid conveyed by the internal fluid passageway within the core aperture.