Thomas, I happen to have the three stave organ sheet from 1956 published 
by Bruin NYC in my hand. My suggestion is to focus on using two 
harpsichords: One player doing the osstinato bass in two hands and the 
other rythmic counterpoint melody with two hands. I can't think of the 
players I'd recruit but I have the two harpsichords and the chart.   
yours Jack Peters