Where to find the motherload replacemente?

Hello Guys,

The mother board of my Asus Zenbook UX501JW - DH71WX is broken and I have looking for the replacement in internet (Ebay, Amazon, Google in general) but I couldnt find it.

Do you know where can I find it? Its been a pain. I also looked in the Asus Store and no luck with that :(.

Thanks