I can offer one very emphatic suggestion regarding the MicroSD cards -- NOT EBAY.
I've not been bit personally, but I've heard the stories. Flash media of any meaningful capacity is usually worth about half the capacity advertised, with dodgy firmware to compensate.
I always buy from Newegg[dot]com but they don't really do volume pricing and they're not a wholesaler which is what you really need. Maybe one of your factory contacts over there has a pal at eg SanDisk? or maybe it might be worth a trip (back?) to Akihabara Market? (Didn't you go there at some point? I can't remember.)