I used one out of a duster for my car it has a plastic base 2 wire one connects to hot and the other connects to the door switch wire no cover just the bulb but you cant see it unless you stick your head under the dash.
Here is one that looks close to original that you could use
http://cgi.ebay.com/ebaymotors/1962...r_Truck_Parts_Accessories&hash=item27b952ec3d
