Surat: Narayan Sai, son of self-styled godman and rape convict Asaram Bapu, was convicted in a rape case by the Surat Court, the quantum of which will be announced on Apr. 30.  Sai was accused of rape by two sisters in Surat. The almost 11-year-old case against Narayan Sai and Asaram Bapu was lodged after…