Whatever class is available at the time.... my preferences change from moment to moment and I generally change class multiple times in a match, so I couldn't honestly tell you which weapon/class I'd choose.
Although I usually try to get the squad leader/commander class if it's available, so probably an MP40 or 41...... probably an MP41.... I like it more than the 40.
I'm pretty sure it's in the game, as I think I saw it in a video.... I guess it depends on what's available.