Source For Oberheim Side Panel Screw and Washers?

[analoglsd]

Looking for a source for Oberheim side panel screw and washers.
Has anyone found an online hardware retailer that carries something that works as a suitable replacement?

[oldgearguy]

In the past I've been able to track down black finishing cup washers (after a few orders and trials to match size).

Stuff like this: https://www.albanycountyfasteners.com/w ... %20Washers

I also seem to recall finding the black plastic insets as well. McMaster-Carr is a good place in the US for various black screws and washers and such.