Does your key work in the glove box? If not, it is probably a valet key. The dealer can order a VIN cut key, but they cannot make one on the spot. So I don't think it's worth a 120 mile drive. Mercedes corporate does require proof of ownership of the car to order a key. So you might try calling the dealership and asking if they will accept a fax of your driver's license and registration.

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Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
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