There are three places for antique-shopping in Manila; the Plaza San Luis Complex in Intramuros, Hall 6 of the Philippine Trade Center (Roxas Boulevarde at Gil Puyat), and Mabini and Del Pilar, between Pedro Gil and Kalaw. The best choice is in Intramuros, particularly for the beautiful old Spanish colonial silver and gold jewellery, but the prices there are between four and ten times as high as in the other places. Go to Intramuros first to see what is available, and then try to see if you can find the same thing elsewhere.
Hall 6 is a vast antique centre, full of stalls owned by independent dealers, so there is no consistency in pricing or authenticity. It is particularly good for furniture, second-hand as well as antique (looking). A lot was reproduction, but I saw some wonderful Art Deco pieces from American colonial times. Also Chinese porcelain (usually fashionably described as from a wreck), tribal pieces (mostly large wooden carvings), small metalware and some jewellery. If something large takes your fancy, there is a small post office for packing and shipping internationally within the complex. Many prices are incredibly low – labour and natural hardwoods are both extremely cheap.