I wish I'd been around here more the last two months but I've been busy. I could have answered this in a second and provided the appropriate replacement fan number as I've replaced over 20 fans in the last two years or so.
We have quite a few 5500's in production and won't be getting rid of them any time soon. It's much simpler and less time consuming for me to replace them than to attempt to have it done under warranty.
The replacement fans we bought do not come with the plug end so you'll need some small shrink tubing, a soldering iron and solder to do the replacement.