Welcome tothe forums. I'm only aware of a handful of Czech manufacturers, all of which were intertwined and located in Cheb, near the German border. While most tricycles weren't serialized, if it does have one, it may provide a clue to the actual manufacturer and year. The post war Czech bicycles I have seen , have had serial numbers denoting the masnufacturer and year. In North America, Czechoslovakia was a common source for private label brands during the post war period, so it may have been contract manufactured and branded for a company. Pictures may help.