Here is a Google Image search results llist for "aluminum clamps for camper shells":http://images.search.yahoo.com/search/i ... per+shells
Should give you some visual ideas of the various confgurations they come in, almost infinite.
Here is the Google search for the same:http://search.yahoo.com/search;_ylt=AsU ... r%20shells
Should give you an idea of several different vendors that have them for sale.
Good luck. Check BassPro and Cabela's too. I believe they have a similar type clamp that is black rubber coated. If I recall correctly, others have used it for a similar purpose to what you intend.
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