I watch birds using a circa 1940 Hensoldt-Wetzlar Jagd-Dialyt 7 X 42 binoculars serial # 693354. I found there are members of the Bird Forum who have this binocular or similar. I am in search information or a users group for repair of these old binoculars. They are quite stiff to operate and adjust and need some cleaning and restoration. Some of the black pebbled surface coating is coming off of the tubes containing the lenses. Is this lacquer or some early bakelite like plastic coating? I still use them for spotting our Painted Buntings, hummingbirds and other birds and animals in our yard. Thanks in advance for help in restoring these beauties to their former condition.