Here you go, my sketch of the riving knife. I’ve forgotten to measure the thickness of the spacer, but I will do that tomorrow. The spacer piece is riveted onto the riving knife, same dimensions etc, and the four holes can be out anywhere, not critical. If you need any other dimensions / any checking just give me a shout. All dimensions apart from a couple are in mm the others are imperial with the nearest metric next to it. I was always taught to put a line through a zero, so it can’t be mistaken for a 6 or 9. So sorry diameter symbol is also used that is exactly the same! Hope it’s clear which is which.
The 7.5mm hole in the middle of the plate can be deleted, it doesn’t do anything.
There is a small bush that keeps the crown guard at the right distance from the riving knife and also provides somewhere for the star handle that clamps it in position to screw into. They were originally imperial threaded, but metric is far better.