Yeah I've got the Fiori-Seguin album. It's quite good. I agree it's the closest thing to a 4th harmonium album out there.
He's got a solo album from the 80s which i only heard 1 song from but it's REALLY 80s. Havent heard what he's done in the years since, but i've heard that it's mostly very different than his harmonium writing style. But his newest solo album was a return to this prog/folky style which was quite nice to hear. Not as good as the 70s stuff of course, but good enough and similar enough in sound that I'd recommend it to anyone who's a big fan of harmonium.