The proper shovels were usually split wood for the D handle portion. Seems to me they were usually bulldog brand as well. You can modify the one you show, or a Cdn tire one to fit by busting the rivets, shortening the handle, and rasping the area to refit the blade or handle (whichever end you choose to work on).
One problem I remember when I used to drive operate these trucks is that some of the commercial shovels had a different arc to them and sat too low in the bracket, pinching and cutting the heater hose.
John Bizal at midwest advertises the correct shovels to install in the M-series vehicles.
http://www.midwestmilitary.net/midwe...cessories.html