If I recall corrrectly, the 8830 came with a few international adapters.
You have to find out what style power outlets are in the country that you are going to. This website lists the different outlets for each country: Electricity Around the World
If your BB charger says INPUT: 100-240V, 50-60Hz, then you won't need an electricity converter, just the plug adapter.
I think Best Buy had some adapters. Target or Walmart may have them too.
As for the SIM card, check the Sprint store or call the 800 number.