Any program to find product key for office 2007?

CarltonWO

I'm getting ready to purchase 30 Product Key  Windows 7 Home Basic Cards of Office 2010. I've done one and had to download it first. Before I could, it asked me to put in my product key and then again during install. Will have to go through this process again  Office Pro 2010 Key or can I use the same exe download and type in a new product key  Office Pro 2007 for each install?