Easy to print Panzer IV Raketenwerfer (Rocket launcher), 1/100 scale, will want some greebling if scaled up. Some details have been changed for looks/ printability. This is a mashup of a few of these I've seen, I don't think It ever really got past the prototype stage. If you want the launcher closed you can trim the props off, but it will look super boring. if you want schurzen the turret will fit on my panzer IV schurzen body.
Scale by 1.56 for gaslands / hotwheels / 1/64
Scale by 1.786 for 28mm / 1/56