Help me identify this tablet Vivax TPC 8150
This is a partial answer and may give you a head start, by way of correct product model details


Retail Branding: SK Telesys
Marketing Name: ITP-R208W
Device:  rk30sdk
Model: ITP-R208W


Source: PDF at this link  List of all devices supported by Google Play

Seems to be a Chinese product called "Thinkle"

This Russian site points to github source when I googled for custom ROM