At a couples Halloween party one year, Buck and I went as good and evil. I dressed in my witch costume and I made him a Friar Tuck-like robe (with a hood) out of dark brown burlap. He went outside and cut a small sapling from the woods for his staff.
I tinted my liquid make-up with a little green food coloring to make my face really eerie. Buck made a cross out of wood that he strung on a leather shoestring and wore around his neck In keeping with the theme, he wore sandals.
If you're game, you two could go as Daisy Mae and Li'l Abner. Those costumes wouldn't be too costly and pretty easy to get the pieces together.
Or, how 'bout Mickey and Minnie. Make felt ears and attach them to plastic headbands, etc., etc., etc.
"As a girl I had zero interest in the stove." - Julia Child
This is real inspiration. Look what Julia became!