Skip the "working links." They are a security headache waiting to happen. If you must have the 2007 interface, look for a used, physical "Retail Box" copy on sites like eBay, though even then, modern free alternatives will perform much better. free office suite that feels the most like the 2007 version you're used to?
: Without updates, your system is vulnerable to malware, viruses, and data breaches.
This post focuses on why looking for old keys might not be worth the risk today.