Be careful with what you end up. Personally, I would only get the original units made by Hella and NOT the reproduction ones, usually made in the far east. The price is a lot lower, but so is the quality.
Hellas run about $400 and you can get them brand new in the box from Performance Products in Van Nuys (Los Angeles area), CA.
Also check e-bay for a good set of used ones; you could potentially save a few bucks, but they won't be as nice as the brand new units.