Where can I find/order cufflinks with Da Vinci's portrait on them?

I live in New York City, but am willing to order from anywhere. My fiancee's 50th birthday is coming up, and he's talked about wishing he could have cuff links with Da Vinci's self portrait on them- I've tried googling like mad, but have come up with nothing. Can anyone direct me to a place or site that has them or can custom make them? Thanks!