I stumbled across your email while I was looking for a replacement for my broken globe of my Hampton Bay fan also....
Well, after hours of phone calls, internet searches, etc. our local Home Depot store gave me the following phone # of "King of Fans"
1-800-330-3267 to see if they could help me. With 1 phone call, they were able to help me with a replacement globe and are shipping it to me today!
You may want to try King of Fans to see if they can help you too!