That's a beautiful sconce. Sure you can use it, but it would put you on a sort of glam path. Is that what you want in that bathroom?

For placement, if you're keeping the sink where it is now, maybe you could do a double or triple sconce over the mirror, and use a pedestal sink (Kohler Memoirs comes to mind) instead of the vanity. I don't think you would have room for sconces on the sides, unless there's more space that we can't see in your pix.

The Venetian Beaded Mirror would look nice with the sconce - see link:

Here is a link that might be useful: Venetian Beaded Mirror