I have to disappoint those who think they have currently a shot at this
record.

While it was hard finding anything solid through the Internet, there
are at least a few hints based on facts that I have known for some
time; I just didn't want to jump the gun by posting something I had
not properly researched.

Here is a short news article from 1984:

    Ein 45-jähriger aus Einsiedeln in der Schweiz nennt sich seit
    Sonnabend stolz Weltrekordler im Dauerdrehorgeln.  Genau 100
    Stunden lang hatte er gekurbelt.  Je fünf Minuten Pause pro Stunde
    sorgten für die notwendige Lockerheit.

What it is saying is that since 1984 the minimum you would need to
crank is 101 hours; for breaks you are allowed five minutes per hour,
not more.

The key to finding this information is my knowledge about an East
German fellow, who in 1983 (so, before the Berlin Wall fell) had set
the very first such world record by playing 48 hours continuously.
He is marketing this achievement to this day (albeit he is no longer
holding the current title)!

I cannot seem to find anything in regards to any attempts since 1984.
My bet would be that even the hardiest of organ grinders was thwarted
by having to potentially listen to the same song for over 100 hours.
Even if you break the record of 100 hours by playing a modern MIDI
crank organ, in regards to a barrel organ the old record would still
stand proud.

Ingmar Krause
http://www.grindorgans.com