Where can I get a "horizontal" sleeve?

I'm looking for an iPad sleeve that opens on the side instead of on top. Also need it to be available online.

The only one I know of is the Hard Graft Heritage Case http://shop.hardgraft.com/ipad-cases/heritage-ipad-case.
Would also love a leather one which is not envelope style (ie. no flap cover, just slip-in style).

Any help would be much appreciated!

Thanks, they're cute!

And love the idea of the Axis case as well (though it's not a sleeve) – clever that it lets you prop it up in both portrait and landscape orientations