Regarding the key: You can buy a blank key shell and have it cut to match your single key. There are plenty of places you can buy an inexpensive blank.
Of course, that will not start your car without having the proper transponder in it, but at least you can unlock the door or turn the ignition to unlock the steering in an emergency. My local locksmith charges about $30 to cut these.
If you are willing to take the transponder out of your good key and place it in the car, you can do this:
https://986forum.com/forums/diy-project-guides/56448-diy-making-cheap-spare-keys.html
