OEM HID headlamps are just flat out pricey no matter what the make or model. When I worked for Ford we had a customer order pair for a Lincoln Mark VIII. They ran $1300 each IIRC. However if you're on your third set on a vehicle that's not that hold, then there's likely a fault that's causing the HID lights to fail. I would recommend that you find the underlying cause of the failures, otherwise you're going to have to keep replacing these lights regularly. You may also want to see if you can retrofit the standard halogen headlights.
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