It's definitely a niche item. Could be a hard sell. You would have to do a bit of networking to find a buyer.
Advertising signs are important to many business owners. They can also be pretty frugal so the idea of keeping the skeleton and replacing the plastic could be appealing. If it's a standard size it wouldn't be very much trouble to make a plastic insert with their company info on it.
You might do a little research on it to see what the cost of new is vs re-signing. Suppose it depends on what kind you've got cause they vary in cost & quality.
Lightboxes & Backlit Signs | Blue River Digital
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