Re: dont use your car for this!!
The key cases for my coupe were badly worn. I transferred the security chip and cut key part to aftermarket cases, and it turned out well. You may want to consider doing this with your damaged key. Of course you will need to get the new key blank cut by a locksmith.
http://www.ebay.com/itm/Chrysler-Crossfire-2004-2008-FLIP-KEY-KEYLESS-FOB-CASE-SHELL-AND-BLADE-/321696112903?fits=Make%3AChrysler%7CModel%3ACrossfire&hash=item4ae6952107&vxp=mtr