Ouch! Aluminum sprockets...some are decent, some are not. I just installed a new rear tire on my XR650L that has Warp 9 wheels on it. The sprocket that came on the wheel is some aluminum alloy Honda XRL pattern, so a steel OEM style Honda sprocket will fit. However, after 5000 miles that aluminum sprocket looks perfect. I've got a steel replacement sitting on the bench, but apparently it's not needed yet.
Hope you guys get the sprocket situation sorted out and continue on with the Lawrence of Arabia trip.