Probably higher, most likely in the records of Gen.Insp.d.Pz.Tr., but I am away from my sources at this moment and am going off of the top of my head. Depending on the timeframe and the particular info you are looking for, sometimes you have to look at all levels from Division up and cross-reference the info. Even then you may not find what you are looking for due to lost records (either destroyed in combat or lost when the archives in Germany were bombed or destroyed to prevent them from being captured).
That early in the war, the records are possibly pretty complete. The records of the Pz.Div. that I am researching are quite sparse during the timeframe that I am interested in, but when I obtained those records, the earlier records were included (though I haven't looked at them in detail). Even if the divisional records contain delivery records, I doubt they will detail the ausf. received. The only differentiation that I have seen is listing them as l (for langrohr - long barrel) or k (for kurzrohr - short barrel). Though it might not be what you are looking for, the divisions were supposed to prepare a monthly Gliederung which usually gave the number of the types of Panzers in the case of Pz.Regiments. Those might be easier to find. Copies of the Gliederungen were sent up the chain of command so could be replicated among Corps, Army, Army Group, etc. records.
Actually, if you do locate the file that has the info you need, it will probably be cheaper to buy the microfilm/DVD form NARA. I just came back from Freiburg (was there in May) and while I found the service quite quick and efficient, one is not allowed to scan, photograph or photocopy any records. You have to request that the archive make any reproductions that you want which gets quite expensive. If you are wanting just a few figures jotted down, then that will not matter, but unless the person you hire really knows where to look, it can take them many days and much money to find it (if it is there to find).
You might want to search this site, forum.axishistory.com, Missing Lynx, and/or forum.panzer-archiv.de using the terms allocations and Martin Block (who has done extensive research in this area) and you might find a list of types of Pz IVs allocated to the units you are looking for for the time-frame you are looking for. If you have time and the determination, you can also go to
http://sturmpanzer.com/Default.aspx?tab ... em=1&sec=1 and look through the guides of the German records held at NARA (which are essentially the same records as those that are in Freiburg). These records guides contain a summary of the records on each microfilm which can allow you to narrow down the files that are most likely to contain the information you are seeking.
Once I get home I will check to see if I can anything that may be more helpful to you. I have a list of allocations that I have found so far on my home computer. I don't think I have one of Pz IVs but will check.