H4 headlight help

I am a bit confused as to the varied price for a set of H4 headlights/trim by Porsche with Bosch lens. Porsche classic sells them new for $404. Yet I also see used ones for sale at prices at or above these numbers.

Suncoast parts has them for $350 each - $700 total
Other eBay sellers have them for $330 each

Can someone explain the pricing of these used and new ones? Is it purely that "original" made back in the day ones are deemed more valuable given they were made in that period? vs new ones that are made in 2017?

Thanks

I'm not a light expert but there are nuances that differentiate early to late. I would buy a restored set of originals from John Audette. Only a couple hundred more (than Suncoast?) and will lend value to your car.