Er, really? Difficult to see how something you can't tolerate for a couple of hours can be regarded as "supremely comfortable". I have no problem riding four hours at a stretch beyond occasionally stretching out my lower back while on the bike, my saddles are not the source of any real discomfort.

OP, the Adamo saddles pictured above were going to be my suggestion, I have known people swear by them after failing to get comfortable on any other type of saddle. I'm not at all sure about the more upright position, though. The classic roadie position tends to mean one puts more weight on the pedals than on the saddle, which may be good for you.