Ok! Here’s what I found out this morning.
That link is the Partzilla parts components page for Kawasaki G5. If you look, there are two different cylinders for them. There’s the early 72&73, then the late 74&75 models. I lucked out and found a late model. If you follow the links to the cylinder, there is a chart that shows compatibility with other years/models. It’s a great feature of Partzilla, even if the part is unavailable. I love their compatibility charts! The late g5 cylinder is compatible with the ke’s.
I double checked the dimensions of mine, and ports too. It’s identical, except it’s cast iron.