Razer Core X Thunderbolt 3 EGPU Enclosure - 10% off Microsoft Australia - $422.10 + Free Shipping
Microsoft Australia currently have 10% off the Razer Core X eGPU with free shipping.
Compatible with MAC and PC - MAC's will require a AMD GPU due to Apple not providing nVidia GPU Drivers.
Your laptop must have a Thunderbolt 3 USB Type C port to be compatible with this.
For the best performance its recommended that your laptop has 4 PCIe Lanes over the USB Type C Thunderbolt 3 connection. The latest Dell XPS 13, XPS 15 and Macbook Pro's all offer this.
If you want more information go here:
To see which laptops are compatable and how many PCIe lanes it has (4 being recommended for performance reasons):