Moved from Old Laptopt to new Laptop, need to install Adobe 7 before I can upgrade to 10 - how?

I have been buying Adobe Acrobat for 17 years.  I last installed Adobe 7, then upgraded to Adobe to Adobe 10, I have my serial number for 7 Standard but not the disk.  I cannot upgrade to the Adobe 10 without the Adobe 7 on the laptop.  How can I download Adobe 7 Standard?  Thank you.