Canadian National Telegraph

Hello. I have an outdoor sign that used to hang in front of the telegraph office portion of a northern ontario train station (photo attached). The sign is two sided baked enamal. The reverse is identical except for the finger pointing is poiniting a different way (Sign is approx. 36in x 19in) I believe this company was created around 1915-1920 when the Canadian government took over failing railroads which became Canadian National Railway. The telegraph portions of these railroads became Canadian National Telegraph & Cable Co. Later it was renamed Canadian National Telecommunications. I personally rescued this sign from the garbage heap in the late 1970,s when I worked for CNT.Any help in valuing this item would be appreciated.Thanks!!