How can I upgrade when my version isn't available anymore?

I own Wavelab 7 and need to download it to my computer again but it isn’t available on the website.
I am willing to also pay for the upgrade but I can’t upgrade without the original version.
Help please

Here is the download link:
WaveLab 7 Updates und Downloads | Steinberg

You don’t need to install the previous version to upgrade. It is sufficient to have a valid license of Wavelab 7 on your USB eLicenser.