Who knows this threaded rod from the cistern?

These threaded rods look like those from viega and might even be a standard part. Alternatively, you could machine something like that, it might take about 5 minutes.

It is Sanit standard and the good thing is that back then I only replaced the cover and therefore still have 4 spare rods I only realized that again when I was just looking for the invoice of the push buttons and saw that they were included in the delivery