A suggested Plan B popularised by William Smith.
If you can judge where the original pivot hole would have been you can use a tool called a Preacher that has three pointed prongs in a triangular format on a plate. The plate has a striking anvil.
You hover the apex prong over the point where you judge the pivot hole should be and then strike the anvil to leave two reference indents on the clock plate. You then broach out the existing worn and distorted hole from the inside of the plate and back fill with a solid brass bush. The bush is inserted from the inside surface of the plate. The bush is filed flat using a bulls foot file. If you don't want to damage the plate surface when filing then you can use a piece of 35mm negative or similar with a hole punched to match the bush diameter and protect the plate..
Once the bush is finished flush and likely invisible to see where it is, you relocate the Preacher on the two reference holes and strike the anvil to create a centre pop with the apex prong to locate the drill for the new arbor hole.
BTW the escape wheel teeth viewed through the hole in the plate look like they need some TLC
Edited By Alan Wood 4 on 13/06/2023 17:46:33