I happen to have the very same clock. I am trying to get mine back into running condition. I just bought it and it has a broken pivot and mainspring.
The 30-day Korean movements will run for many years if properly serviced and oiled, but when it comes to repairing them they are a nightmare. Pivots break very easily, and the brass in the plates and gears are much thinner than the older clocks. With sucn strong mainsprings needed to keep them running for a month, there is a lot of stress put on these gears. They will wear quickly if not kept oiled.
However, if you keep yours properly serviced, you will probably have no problems. I believe these were made in the 1970's but I am not positive.