I've been through the mill regarding the steering rack for my '05. I'm sure its the same as the rack in your car. I've been through 4 in the last few months. I think the current one in the car has a small internal leak but I can't prove it. I just have to add a small amount of PS fluid every week or 2.
Anyway ... there are no new or rebuilt units available. I started out with a "rebuilt" unit but it's just marketing BS. The racks are NOT rebuilt. The reason I've been through 4 so far is because they are NOT rebuilt. As far as I've been able to find there are no parts to rebuild the racks with. The so called "rebuilt" units you'll find are merely cleaned, painted, and shipped. You'll see claims of "tested" but that's not been my experience. The first rack was leaking a little when it was installed. A few miles later it was leaking a lot. The 2nd unit had an internal fault in the control valve and it was very hard to steer. The 3rd unit had a failure in the VES (the electric motor) and caused a DTC as soon as the car started up. We'll see how long the latest one lasts.
Whatever you buy will be a used unit, it's simply a matter of how much you pay for it. Even if you purchase a "rebuilt" unit with a warranty it won't last. It will probably have problems as soon as it's installed. The problem is the constant replacement. If you replace them DIY it's a lot of work over and over again. If you have them replaced at a shop you'll pay for the replacements each time. While the part may have a warranty the labor NEVER does. And it's expensive. The shop that did mine got tired of replacing the racks and despite the part warranty they don't want to replace mine again. When the current one fails I'll have to find another shop to have the rack replaced. Replaced with what is the million dollar question.
There are engineering firms that will make custom steering racks but I have no idea if that's a possibility or not. There are also YouTube videos regarding making a custom electric steering replacement for a steering rack. This seems appealing but I have no idea how much effort is required for such an experiment.
Sorry to be a downer but this is not a simple problem. I wish you better luck than I've had.
