2003 Audi A6 - Broken Key
 

So i recently purchased this 2003 Audi A6 Quattro from a private seller, the car only came with 1 key as he didnt have a spare. The Key recently broke with the Key blade being seperated from the plastic part that contained the chip (I believe), and I still have the key blade which can be inserted into the ignition, however ive lost the plastic (chip) part of the key and the car will not start for more than a second due to the immobilizer ( I believe). Im trying to figure out what the best course of action should be, would it be possible to have the key re progammed not involving the dealer, or would it be best just to go through the dealer to get a new chip.

-Thank you