Thanks to Mike and Brad Z. for giving me the correct info on the type of tube needed for a NATO Michelin Tire! With their help, I was able to find the correct type of tube and flap, with the correct style stem, by asking for a "lowboy trailer radial 11 x 16 tube.

These tubes are made by International Tube and Tire (ITT) and have the same stem as the Non-Radial 9 x 16 tube VPW sells. They are 9/10/11 R15-16 Radial Truck Tubes, ITT Product Code 11430, with Stem TR75A, which is a Brass Stem, with a 90 degree bend that just comes to the inner edge of the Split Ring, or Combat Wheel ring, so it doesn't hang out where it can be damaged.

The flaps are by the same manufacturer, and are 8 x 16 radial Flaps that are the same thickness and width as the original Michelin flaps that I took out.