@Positive Change and @Thaimonk.
I found a similar one Monju Bosatsu (as displayed by Positive Change) in the Tokyo National Museum website. It is beautiful and exquisite and so it is a real museum piece that may be one of a kind. Perhaps, we can look at replicas of this old statue. Anyway, I can't seem to embed the image from the website and so I leave a link to the site here:-
http://www.emuseum.jp/detail/100434/006?word=&d_lang=en&s_lang=en&class=3&title=&c_e=®ion=&era=&cptype=&owner=&pos=25&num=8&mode=detail¢ury=Here's the description from the museum site:-
Important Cultural Property
By K?en
5 statues
(Some of the works of theManjushri (Monju Bosatsu) on a lion, and standing statues of attendants )
Wood, colored, beaded eyes
Manjushri: total H193.7, statue H46.1, king of Khotan: statue H69.5, Sudhana: statue H46.2, Taish? R
Kamakura period/Bunnei 10 (1273)
Formerly kept in K?fuku-ji Temple
Tokyo National Museum
C-1854
According to a note, which says that these images were created by Buddhist sculptor Koen, written on the head of the lion on which Monju (Manjusri) Bodhisattva sits and documents that are owned separately, from the images, by Daitokyu Kinen Bunko and others, it is clear that these images were created in 1273 by Koen (1207 - ?), a sculptor of Buddhist images, who was a successor to Tankei. The person who made the votive offering for the creation of these images was Gyogen, a priest of Kofukuji and these five images were enshrined as the principal images of worship at Kangakuin, which was established at Kofukuji Temple in 1285, twelve years after the creation.
This group of images is called Godaisan Monju or Tokai Monju and based on the icons that emerged from the Godaisan Faith, faith in the holy mountain (Godaisan) of Monju Bodhisattva, in China. However, the representation of crossing the sea is unique to Japan. In these images, it is represented by sea waves, which are engraved on the upper surface of the pedestal frame. The five topknots on the head of Monju Bodhisattva and its boy-like appearance correspond to the description of "child-like appearance" written in sutras and show that the wisdom of Monju is as pure as that of a child. The child image among followers is called Zenzai Doshi. In the Kegon Sutra (Avatamsaka Sutra), he is described as a child who visited 53 virtuous wisdoms and practiced and completed all austerities required to become a Bodhisattva.