Worth a try
Since all the countries on your trip use the same alphabet as us, it's not as useful as in places such as China or Russia. On an enforcement stop, I've been given an International Driver's License from some eastern European country with a different alphabet and it was a big help. It may help down south and certainly couldn't hurt. I'll spend the $15 for my upcoming South American jaunt. Just as an FYI, the international driver's license is NOT valid without the license of the home country, at least here in the USA.
KTM 950 SE, KTM640 ADV ( Hibachi, risen from the ashes)
KTM520EXC (broken), KTM 400XC (the replacement)
Honda ST1300 ABS (newest addition to the stable)
STOC #326 IBA #217