Reinstalling original aoe2 the conquerors having lost cd rom?

As you can clearly see from the title I played aoe with the gold edition as a child. I recently bought the hd version on steam but I noticed that I couldn't play online due to my terrible italian internet connection...still I have lost the age of kings cd (but I have the old activation code), do you know any way to reinstall the original non hd game? If not a way to download it safely? I really wanted to play it with Voobly online