Dundas Street in Mong Kok, right next to Sino center.
There is a Toysmart shopping mall with many toy stores, recommend the one in basement level 2 near the end. It has all the 1/48 Yamatos.
Also, there is a 2nd floor shop on Dundas street across Toysmart.
Great selection, but the price is not rock bottom.
$950 for VF-1J Super is the cheapest I have found. Good luck in toy hunting.