Is there an already-existing piece of commercial or academic software that can
There are two options that I have worked with previously and would recommend.
It is a commercial offering that uses multiple OCR engines and voting to determine the best result. It is machine print only. Last time I used it they had 6 engines. Contact Alex Dahl.
I have used it in a major project scanning 20,000+ pages per day.
RecoStar uses voting and can do handprint and machineprint.