Sharing a Vimeo video that plays in a lightbox

Hi -- on http://www.newmediaadvocacy.org/ there are Vimeo videos embedded on the page that play in a lightbox when you click on them.

I'd like to insert a "Share" button or link that allows viewers to share a non-Vimeo URL to the video on the site. Right now there is a share link but that only provides a direct link to Vimeo, and I'd rather not send people to our site, not Vimeo,

My only idea is to create a new page for each video which would produce a unique URL. But how would I make that URL appear within a link in the lightbox?

Thanks for your help!