Headphone listening can never make a live organ justice of course, but I'll second that the GS-1000 really make those deepest organ notes come to life.
There's no particular headphone which I find particularly spectacular with the organ. The sub-bass rumble is just missing. On the other hand, a decent pair of full range floorstanding speakers (eg 8"+ woofers) will get you 80% there. Add in a couple massive subwoofers and you'll be 90%+ provided the recording is very good.