Here is the guy who makes all the fake route 66 signs.His ebay name is beautyrest1 . I was his UPS guy for a while. He sells them as repros, but the buyers resell them as real. Only makes small batches now. He once sent some to several well known auction houses, everyone authenticated them as real !!!! I believe he made signs for movies (Hollywood) for a while. I know he uses glass marbles from the far east because they are hand blown. Another link to one of his "period correct" repros

http://www.ebay.com/itm/1930s-STYLE-LOS-ANGELES-CITY-LIMIT-SIGN-W-CATSEYE-REFLECTORS-LG-32-TALL-STEEL-/391362689036?hash=item5b1f08b80c:g:9zoAAOSwL7VWkysw