I don't know if "historical" mashbills are being added to the whiskey tree yet, but I can tell you Michter's from Schaefferstown used:
12% barley malt
to make Michter's Pot Still Whiskey. As for the barrels, all I have seen have a pretty heavy char inside them. I'm not sure of the bourbon, rye, and corn mashbills, but I could ask Dick about them next time I see him.
I think the problem with incorporating the mashbills of dusties is that it could spiral into a listing of every bourbon mashbill ever made. It's more practical to stick with bourbons in current production.
HOWEVER, now that you've posted it here, it's forever in this thread. Which I think is pretty cool.