This appears to be a custom combo MBM38A1 body. I wonder whether the seller knows it or not.

“1942 Willys MB 4×4 WWII model. The body looks rough but is adequate for hunting or farm use. It has had the windshield glass, gas tank, and one rear axle replaced. It has good tires. The engine, transmission, transfer case and drive train are all original as far as I know and all work well. The engine runs great. The alternator needs to be replaced. I have always charged the battery and use it as long as it lasts. We can discuss delivery. 512-446-2382.”

http://waco.en.craigslist.org/cto/1480523308.html