If you have a laptop you can use ForScan to program your new keys to your Ford, regardless of how many other keys you have in your possession. Buy the keys on Amazon and take them with your good key to any Home Depot or Lowes and have them cut to match your working key ( usually free or minimal charge...). Then use ForScan to program them to your Expy once they're cut. They would have to be cut for the dealer to program them anyway, so that is always the first step. After the key is cut try it out in the Expy's door lock to make sure it's cut right.
I would suggest these keys, because they have slightly smaller FOB actuation buttons and are less prone to accidently triggering the panic button or popping the rear glass when turning the key to start the vehicle or any other time.
Ford Key FOB on Amazon
Free ForScan Downloads
You can order a USB to OBDII adapter cable from ForScan or Amazon to use with your laptop.
ForScan OBDII Adapter Cable on Amazon
Also many locksmiths have the capability to cut and program your new key to your Expy, you'd just have to call around. But they're generally cheaper than the dealer and they guarantee their work. ( If you don't feel comfortable working with ForScan and your laptop on your vehicle...)
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