Well, I just recently dropped my Tamron 17-50 2.8

There is a little rattling in it and I see a black something when I look through the lens. It seems to take pictures fine though :S except the AF seems louder. And I bought this lens in Hong Kong a few years back.
My question is, do you think it's repairable? And if so, any place locally I can take it to? If not, I'll have to find a repair center. Will they service a lens from overseas?