Help finding part

Help finding aluminum cover plate for magneto hole

Does anyone know of a source and part number for the cover that goes on the accessory case in place of a magneto? I’m using a Lightspeed Plasma III ignition with the flywheel timing sensor, so no mag on the right side. I’ve got a persistent oil leak where the current cover mounts over the empty magneto hole. I’ve tried new gaskets, anaerobic gasket sealer, new hold down tabs, etc. and still have the leak. I’m thinking that the aluminum cover might have a slight bend that’s allowing oil to seep out.

Here is a picture of the Plasma III kit. The red arrow points to the part I need. Any help with a source or part number would be much appreciated.

it was long time sins I removed cover
if I remember correctly it have o ring to seal not gasket
should be easy one to make on the lathe if you have one or
if you know any one have lathe

my oil leak was from the screws that previous owner used to hold those covers down
you must use stud's with interference fit