Board BOM?

I am really looking forward to develop new devices using X15, as TIs devkit is more oriented towards industrial IoT, while i see a great potential in media processing. But what bugs me, is that i cannot find any informartion on how much of the cost of the board is the Sitara chip itself (as most likely ill be using a diffrent model of CODEC chip and PMIC)
Could you tell me where can i find such information?