New mechanisms can be bought, but not the knobs individually.
A quick bit on CAD could remedy this. I kept as close as possible to the original as can be seen below
The knobs can then be painted with any sort of paint. The letters are inlaid so the paint won’t just come off.
The mount then needs to be heated for 20-30 seconds before presson on the knob firmly. I did this on a gas stove.
Links to the files here – https://www.thingiverse.com/thing:4509119
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