Yes, I should have looked better. I was talking standard dashlights but you mean the bulbs for the lightfixtures that lights the panel, right?
If you make some pictures of how the lights are build in the fixture and how they are powered, maybe I can give you some idea how to modernise them.
Complete pictures of the fixtures themselves can help too.
Edit:
I couldn't open the second link at first but later I could. Now I understand what you mean.
Maybe something like this is an idea,
https://www.mijn-artikel.nl/Webwinkel-Product-338925624/Universele-Pre-wired-12V-24V-36V-10mm-Waterdichte-LED-Dash-Panel-Waarschuwingslampje-Metaalen-Indicator-Lamp.htmlYou replace the complete fixtures then but you will have working dashlights. Your dashlightfixtures are just to old and the bulbs are discontinued. The only thing you can do then is visit pars sales for classic cars and hope somebody has some bulbs laying around that work. but then again, for how long.