Go to your GMC dealer they can get one
you will have to replace the complete ignition switch with a new one.
You will more than likely have to get a new ignition and key for it.
According to my owner's manual you must contact a BMW dealer to replace the key.
If you don't have the code, you will have to replace the lock cyl. They pop out if you know the procedure (and come with keys).
If I understand correctly you lost the key and the ignition still works. If this is true go to a dealer they should have a replacement key to buy.
Don't replace anything. The dealer can make you new keys by using the Vin # on your vehicle.
There is a lock ring on the inside of the dash where the switch connects. You need to remove this lock ring to remove the switch from the dash.
A Mazda Dealer's Parts Department can cut a new key from the car's VIN number.
You ask if your friend has one
Unless you have lost the nozzle there is no reason to ever replace it. It is probably stopped up. Take a needle and unstop it.
Lost ignition keys for newer vehicles can be obtained from the vehicle dealership. Lost keys for a 1978 Honda Accord will require the replacement of the ignition.
Ford Dealership should be able to help. If not you may have to replace the ignition and steering column .$$$.