Aaron,
* Grade II? If a no letter prefix, wouldn't this be a Grade I, S/Var. 2 per Jan's Axis Pistols breakout??
* Anyway, my SWAG for a no letter #9704 = late in Nov., 1940. My linear production assumption with a restart in the late 2nd Qtr, 1940 suggests 11/27/40; but, so much was going on @ Radom that it is a wild guess to suggest a finite date for this early of a pistol.
* Example: R. Berger, in his booklet The Radom Pistol (1981), Pgs.96-97 states exact Quarterly Radom Production figures for 1940 & 1941 were found in Austria(Steyer) after WWII ended. The figures are 3rd Qtr,'40=1583 units, 4th Qtr,'40=10656 units, & 1st Qtr,'41=5221 units. The question arises how this Radom Production included the remaining (2000??)five digit Polish Eagle slide Assemblies into the time line, when German production of S/N 01 began, and was the Assy of these two groups sequential or intermixed. Mr. Berger suggests the large jump in the last Qtr.,1940 was as a result of the Germans using up & assembling all the unfinished Polish (Eagle-my word) Production. Did #9407 make the 1940 cutoff or was it pushed to 1941? Looking at the 12,239 units produced through the 4th qtr.,'40, your #9407 could fit with approximately 2000 Eagles. But, when within that 4th Qtr is still a wildcard.
* BTW: If yours is actually a Grade II, 3 lever, no slot, please report the letter prefix & we'll make another run at this for ya.
* Trust this responds with some insight to your question.