How? Where?
I have the 2017 MBA 15" . Hate how the thing crashes all the time from using USBC peripherals... arghh..
If that doesn't work, go to Mac > Macbook Pro > Buy > 15" > Scroll down to the 3rd option.
They come in and out of stock though.
I'm in IT and order these all the time for engineers and sales folks; it's much preferred over the new models. ;)
https://www.apple.com/shop/browse/home/specialdeals/mac/macb...
If that doesn't work, go to Mac > Macbook Pro > Buy > 15" > Scroll down to the 3rd option.
They come in and out of stock though.