I've been in SIngapore for 3 days, and today I went to Singapore's toys'r'us at Paragon mall (Orchard Road)
there I spotted a Tamagotchi v4.5 just like the US edition, I began to look closer and found that the Asian v4.5 use a star chain like the Uratama
so I bought it, I checked the other TRU and they have some too ^^ so good news for those Asian's out there
btw. they're imported from HongKong
and there's a Bandai-Asia sign too.