How much do car companies charge to make a duplicate key?

Brighton Evans questioned:

I recently bought a strain new Hyundai car with a key which has the clichéd diffident keyless access et al. I lost one key and am wanting to make another. They say I cannot make a duplicate in another key cutting store and that I can make it ONLY with Hyundai in view of the fact that of the diffident keyless access et al. They are charging me Australian $380 odd. I am just wondering if anyone has had similar experiences; how much they were exciting and if here are any ways around it?