If you still have your serial/activation, you can download it here: https://helpx.adobe.com/download-install.html and then use your old activation info.
If you don't have them, and you registered your product with Adobe, you should be able to log in to the Adobe site and recover them under Plans & Products.
Adobe will only replace current version media: Obtain replacement CDs, DVDs, manuals
If you don't have the serial/activation and you never registered your copy, I'm pretty sure you're stuck with buying DWCS6 or subscribing to the Creative Cloud.