Your bass was "made for the trade". Distributors, stores and schools would contract for a manufacturer to make instruments for them, usually from a design the manufacturer was already making. The buyer would then badge it (i.e.,put a name on it). In Japan in the 60's and early 70's it was common for more than one manufacturer to make very similar instruments. It also was common for manufacturers to sub-contract all or part of the the instruments to other factories. So, while the owners of the Conrad name may have contracted with Matsumoku, they probably did business with other makers. Even if it was made by Matsumoku, the neck, body, etc, may of been made by another factory.