try the volks hobby store near akihabara station, the first floor is a store with rental cubicals, the 2nd floor towards the back has a 1/6 section of parts and full figures. you could also go to hot toys' toy sapiens store in harajuku, its alittle far from the station through side street way past takeshita street. you can also check out any mandarake 2nd hand store around tokyo, like akihabara, nakano, and ikebukuro.