Hi! Think you can try Cathay Photo at Peninsular Plaza or John 3:16 at Funan Centre.
I have 2 Lowepro camera bags, one for 2 cameras and one for single camera. The prices are reasonable and most importantly, the design is user-friendly and can last quite long.I like the protection that the bags provide, feel quite safe when I load my camera in. Not sure of other brands, do try them out before you buy.
cathay carries the beltpacks ya? the last time i went down i only saw the normal sling ones.. ended up buying a crumpler, now i really need to get a beltpack type... going on a trip and i'll be backpacking... so no space hehe