MAS do have an annual commemoration ceremony at their former training school compound at Subang. There is a plague there honouring the crew of that tragic flight. However the passengers has an actual memorial built somewhere in the state of Johor. I believe the yearly ceremony in Johor is handled by the MAS station office in Johor Bahru. Maybe you can google up the MAS JHB office for their contact number and ask the staff there if there is going to be a major ceremony for the 35th anniversary this year end.