Can only assume that a previous owner has used something like a pale coloured enamel paint to create these 'eyes' - they are on both sides of the head.
At least I've not seen them previously on the few swans I've had, but given all away so nothing to compare this with - and assume factory didn't give vision to a few individuals. Height is about 8" (c.200mm), which from memory is a not uncommon size.