Help me with this rarity

[Arqueologia_Digital]

Hi, i need some help with the rarity of Pengo for the Game gear, because i found this game and i don´t want to buy it until i know how rare is it. The man said me that the game is chinese, not japanese and the box isn´t the same as the pic. Look the auction here...
http://www.mercadolibre.com.ar/argentina/ml/org_prod.p_main?it_s=MLA&it_n=6637820

Thanks to all

Matías