Update September 2017: Yeah! I finally managed to locate a shop in Petaling Street that are selling the wooden mooncake moulds. View the article in this link: Shop selling wooden mooncake and ang ku moulds in Petaling Street
Update in August 2017- I have went around to try to look for wooden molds for mooncake baking as I have received a number of inquiries from users. It has been unsuccessful and if there are any shops selling, the wooden moulds are very expensive (ie RM69.90).
An experienced shop owner informed me that wooden mooncake moulds are very hard to find. Reason being is because the wooden mooncake moulds are manually carved. However, there are less and less skills craftsman carving the mooncake shape out of moulds due to lesser demand as increasingly no one seems interested to make mooncakes anymore.
Another place where you can try to search (but no promises) is at Petaling Street (Chinatown) whereby there are a few shops selling dry items like nuts and other supplies located near Popular Book Store. I remember my mom bought her mooncake moulds from there (but that was years ago).
For those who want to try their hand to make their own traditional mooncakes like lotus paste or kam thui, you would need the durable mooncake wooden moulds.
In case you need to look for it, I have seen a few being sold for RM20 each at this shop located at the top floor of AEON BIG (formerly known as Carrefour) shopping complex: