Hi spacestrings,
To be honest, I don't deal much with WGA Kits, so I am unsure of what the prices are and if a WGA Kit is even available for Office (there should be, but I don't know for sure).
The easiest way to find out the price would be to go to
http://microsoft.com/genuine and click the 'Validate Office' button. Once Office fails Validation, the site should offer you a WGA kit, follow the link and Pricing should be provided to you, at that point.
Another option is to go to
http://www.microsoft.com/genuine/selfhelp/OrderHelp.aspx?displaylang=en at the bottom of the page, select your location and it will provided the contact phone number (or email address) for the WGA Order Support office, for your area. I am unsure if they can place an order for you, but they should be able to tell if there is a WGA Kits for Office and, if so, what the prices are.
Hope that helps,
Darin MS
