I had a chance to play one of those low G accordions. Hardly any bellows movement and that thing growls. I have a very old Eagle in F that I picked up for next to nothing. Very high. Can't imagine a G box above that without driving all the neighborhood dogs crazy.
Steve
Similar to what Steve just mentioned, I have a G box and the note are at least an octive above the G scale on my C box.
It is not a Cajun accordion and only has two reed banks. It is old and of Chech manufacture. I suspect it was use for traditiojnal Eastern Europian music or perhaps Irish jigs and hornpipes.
It was an "I will trade some of my junk for some of your junk" swap and should make an interesting restoration project someday.