I saw these the other day on ebay. I wonder if a light like this might be the ticket. It projects the light sideways. There are similar lights sometimes referred to as mushroom lights that project the light to the side off of a curved surface, but those usually project forward, as well. The BA15S base would require some dremel work and replacing the socket in the plastic mount, but that has been done.
http://www.ebay.com/itm/251589102554
Salty