Depends on how much you want to spend Larry. Plenty of expensive Hornet, Ultracast,etc figures around, but it may be a waste if you only want a half figure.
The DML 6014 German Tank Crew, 1944-45 has a driver figure (figure 1) that might suit. It has the peaked cap (not side cap), is a torso and both arms are lowered with the forearms extended as if holding the steering levers. The figure is depicted in camo tunic, so it is SS cut, but can be done in basic black with no problems.
Alternately, The DML 6028 Tiger Aces (Normandy 1944) set comes with a figure (figure 2) cut off at the knees, but has one hand up, as if holding onto the tiger square turret hatch. It may fit the Panther Cupola as if the hand was holding onto the MG ring. The other arm is angled down and forward, but maybe if you removed it at the forearm it would be hidden under the cupola lip. (See my page on Derek's build site for a pic of the box top as this is the figure kit I am using for my Panther). Several of the other figures in these sets would suit other poses.