here's a quick mock-up I made/edited with a picture of Leather from google.
I'll do some more work on it later, this is just a quicky thrown together in a few mins, which gives you front and back with a spine that can be either folded to make the card a bit more square when stood up [ (obviously centre bit would be much much smaller)
or fold through the spine for the usual < card shape.
http://i4.photobucket.com/albums/y10...invitecopy.jpg