Bluepower is Swedish company that designs vehicle specific head units. The units mate up with steering wheel and rear view camera controls without needing any adapters, at least for the Euro vehicles. The radios are available with either North American or Euro radio bands. The U.S. price should be about $540, depending on Euro - U.S. currency valuations.
I think Roadrover manufactures the units for Bluepower. I don't know if the Roadrover units are the same, or Roadrover cuts corners on their own brand. Also, I don't know that you could order a single unit from Roadrover. (I think Roadrover is looking for distributor customers, not single retail customers.)
You should be able to order the North American radio band unit directly from Bluepower. Because satellite radio is a U.S. only item, it is not available on any Bluepower head unit. Also, I don't know if the steering wheel controls and rear view camera hook up directly to the Bluepower. The nav should work fine; just load whatever compatible system you want to use through the SD card slot.
If you're willing to give up Sirius, this looks like it could solve all the existing head unit problems and theoretically hooks up to everything just like the stock head unit.