Quality Porsche Parts prob has them cheaper than you'll find. People usually sell them for around a grand or more. Mine are mint and I had them for sale once just so I could upgrade to C4S headlights. Never sold.
But here's a link to one headlight.
02 Boxster s rwd Porsche 986 R Front Headlight Head Light 99663105807 33 628 | eBay
I'd do the retrofit tho. You don't want these. They look ok, but not as nice as those retro's. And the light output sucks. Worst Projector I've used. Honda S2K Projectors blow them away. Mercedes blow them away.... hell everyone does.