Hello, I can confirm that this piston is compatible with the Hero model as I have installed it on mine. In fact, unless I am mistaken, it is compatible with all noblechairs.
However, to remove the old tube, it's quite complicated, I advise to hold it in a vice and hit it with a hammer to get it out.
Unfortunately, we currently have no information about when the item will be available again and when we will be able to deliver it. The supplier himself is still waiting for a subsequent delivery from the manufacturer and for this reason he had to set the delivery date to unknown. As soon as something changes in this regard, we will post it here. Sorry.