A new icon theme called Box has landed in Lubuntu 12.10 Quantal Quetzal.
The theme is inspired by elementary icon theme, which it "inherits" (meaning that some elementary icons are used by Box) and the Faenza "box" style.
The theme is not 100% finished, but is already available for Lubuntu 12.10 users. Box icon theme can also be used on older Lubuntu releases, and not just Lubuntu, it should work with GNOME / Unity too, though it's not optimized for them.
Download Box icon theme (.deb) - also requires the elementary icon theme
via Lubuntu blog