The International halftracks were made for lend lease during WWII. They are very common in European countries where the White, Autocar and Diamond-T are common stateside. Your best bet is locating a set in Europe or Canada. They have a lot of International halftracks. The reason for different headlights is the same for the different drive train the International uses, supply. The government wanted a different source of parts for the Internatioal track and that is why the difference.
Steve A.