My friend Jeff sells these on eBay. Nice aftermarket HID's that a couple of forum members have purchased and indicate are very good quality.
Porsche 986 Boxster 996 MK1 Black LED DRL Projector Headlights | eBay
However, you may be able to find OEM Porsche litronics for sale for less money if you're patient and you can buy the left or right one first and keep looking for the other side.