The piezo ceramic actuators finally arrived. They are miniscule. For my first tests, I glued them to an aluminium plate and glued a mirror on top. I hope they work as intended, because I only have a few. The mirror I am using is a regular glass mirror, and has to be replaced with a dedicated laser mirror in the future, but it will be enough for testing purposes. I haven't made any calculations so it's very much possible that this design will not work at all. All I have to do now is to find a high voltage source.