They have to charge the installed price for you to get the warranty, though. Why pay that money and take it to install it yourself? I'd figure out a way to get it there.
When I sold my Bronco, I drove it illegally to the viper dealer and had the alarm uninstalled (the alarm was worth more than what I was selling the truck for). I think I paid $100 to have it re-installed into the Durango. If I had moved it over myself, I would have lost the warranty.
You could always try ebay, but I guess that doesn't really helpy you with the warranty part...