I replaced my seat with a saddlemen gel seat in November 2010 after returning back to a much cooler climate than Karratha, WA. Having worked in Port Hedland for 18 months, then two and a half years in Karratha my original seat's leather cracked up with everyday use and some very warm days in excess of 40C plus.
The seat was found at an E-bay store in the USA and cost me about $500AUD delivered to my door. I forget the local Honda dealer price but it was a lot more than that.
https://www.saddlemen.com/stealth%e2%84%a2-seat-st-sport-touring-series-honda-1
For a little extra touring comfort I made up a sheep skin seat cover.

The new seat is a lot better than the original for both of us. I sit a little lower and have some lower back support while my partner sits a little higher which gives her better visability forwards.
I have yet to try this seat in touring mode as in the last year I haven't done much more than local riding. A few trips to visit family and friends etc. with those averaging 500km return in a day or a weekend. But that may change next year as may have work in Kalgoorlie early next year.