Hi Sam, Yes keys are a total rip off. They will all be in the same frequency range and have a xtal for a specific frequency. As well as the frequency they contain an e-eprom that is programmed with a code that works the remote functions in the car. Some makes of car keys also have another chip in them which the dash interrogates when it's in close proximity.
Unless anyone knows differently I think the main dealer is the only option or risk buying one off ebay that may or not work, but the e-eprom will still need programming to the same code as your existing key. Perhaps else someone has found a workaround?
I wish you luck.
Mike.
