I just purchased an '06 LR3 with the upgraded stereo but no nav system. Is there an after market nav system that will fit in the open space of the dash or is it possible to get the Nav system that originally came with the car and have it installed?

I asked a guy at Best Buy about it and all he could tell me was replace the entire system with a new one. That sucks. I've looked on Ebay for the Nav system but haven't been able to locate one.