O Gauge Guy,
I can't comment on the maker of those lamps, but as far as the size goes, they're a good, reasonable size for O scale (1:48). A 97mm tall post comes to ~ 15-1/4 feet tall or 4.7 meters tall. In other words about 1-1/2 stories tall, fairly close to typical light posts back then (or now).
If the tops are glued on as others have stated, gentle persuasion with a sharp knife or similar at the joints, is usually enough to pop them open. Watch your fingers though (one emergency room visit later, I can tell you why).
Tom
