I like to share a lot of projects on PCBWay, and so do a lot of other creative people in the modding community. So here's a quick guide on how to order from them if you are confused.
This is my reproduction 1:1 GBA PCB. First double check the description for any order instructions
It says to order at 1mm and ENIG.
1mm is the board thickness and ENIG is the surface finish of the board. For something with conductive button pads or fingers (like a cart), it is VERY important you pick ENIG.
Click the add to cart button, and change the surface finish and thickness
You can also remove the order number otherwise you will have an ugly stamp on your board.
You can change the board colour by choosing a solder mask colour.
You can find my projects below
https://www.pcbway.com/project/member/?bmbno=8E052D1F-B6E0-47