Cut the data into the surface of a chunk of highly reflective and stable metal. Lob that into a high orbit. It will blink out your data from on high with nothing more than the incident light of the sun to anyone with a basic telescope, or even their naked eyes if it's big enough.

Obviously the details would be rather complicated. How is the data encoded? Morse code? Maybe ok for 500 years assuming the language it decodes to stays around. You could treat it like the messages we send to deep space and make it only pictograms. But that might take some effort if you are trying to bemoan the complexity of k8s for generations to come. That brings up the question of what are you trying to say? Do you already have something you think is worth saying across deep time? A person could spend their life solving that problem before they even get to the engineering challenges...