I made the picture of these 2 Kunlun
figures in the Royal Ontario Museum
Taken from: James K. Chin; Guangdong Archaeology and Early Texts
Race and Racism in Modern East Asia: Western and Eastern Constructions
These children the poem says sailed from an island in the sea on their way to China (haizhong zhou) a barbarian guest (manke) (obviously a foreign merchant) had bought them in Yulinzhou.
The poem is preserved in the compilation Complete Tang Poetry (Quan Tangshi).
Home to the Kunlun is the islands amidst the Southern Sea;
Yet, led forth by Man visitors, they have come to roam Han lands.
Parrots and cockatoos must have taught them speech,
As, riding upon billowing waves, they first entered through the Region of Teeming Forests.
Gold rings once dangled luridly from their ears;
Which conch-spiraled hair, long and coiling, they still refuse to bind their heads.
Black as lacquer is their flesh and skin received from nature;
Half-stripped of tree-floss garments, they stride about with bodies exposed.
After more examples James K. Chin concludes that only from mid-9th century can the Arabs and Persians have shipped some Africans to south China. All earlier mentions of Kunlun nu should apply to Southeast Asian Negritos.