Cloud 9 gel seat w/ rubber "springs"
I just got a Cloud 9 gel seat w/ rubber "springs" at Amazon for $25 including shipping. The "horn" is a little wider than I'd like, so I might return it (not decided yet), but it is a very comfortable seat besides that. This might be all the comfort you need. I would try it, or any cushy seat w/ springs or rubber "springs", as an option. Or, Ebay has many suspension posts for about $10-15, I think. Good luck!