Try this website. This is the Sunbeam site with links to the parts supply companies they recommend. There are small companies out there that can do the repairs for you.
They would normally sit in a groove under the turntable with a groove on top to hold them in place. I was hoping to find a Parts Schematic Diagram, but that model seems old and rare.
https://www.google.com/search?q=sunbeam+vista+mixmaster+423a+parts+diagram
Dave's Repair may be able to help as he seems to be the expert.
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Question edited for clarity.
Question moved from Sunbeam Cars
There are no instructions on disassembly because it is so old. There will be screws underneath. Oil will be grease that is degrading.
https://www.google.com/search?q=sunbeam+oskar+4816-8+disassembly
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