I’m hoping one of you guys can help me source a load of replacement rubber washers for my son’s dining chairs.

They are 21mm OD, 15mm ID and 5mm thick. They act as shock absorbers between the trendy plastic bucket seat and the cantilevered legs.
I’m assuming they need to be soft as they squeeze up between two plates. This example is hard as rock and cracked.
I need 24 (6 on each chair).
Thanks in advance.
Steve
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