I’ve spent the last couple of days looking into MaterialUI. It seems really good however there are very few examples of a layout wireframe. After digging through Github I came across the following CodeSandbox:
There are a number of other themes and templates available (such as the amazing Material Dashboard) but they are all very in depth and not really suitable for a quick prototype or mock.
Thanks to Luke Peavey for posting the answer on StackOverflow. It definitely deserves a lot more views: https://stackoverflow.com/a/50312721/522859
Hopefully, this will be able to save someone else a bit of time!