Bed racks and fabric covers

I've seen bed racks that work with soft toppers, but are there any "soft topper" type materials that go around a bed rack? I was thinking of making something custom to add visual security to my bed rack. Some cloth/canvas panels that go on the sides and the back of the bed rack to keep people from peering in. Something that would have cut outs or slits on the back so I can still hang my bike over the tailgate. Anyone know of a company that makes something already or is this going to be a custom thing and I gotta learn how to sew?