Gary,
Give me a call. I have a Session harness on order at Ocean Rodeo. We can put an order in for one for you if you like it at a decent price. They are a bit more expensive than regular harnesses, especially if you get the shorts to go with it (the leg straps fit into slots in the shorts) but they can be used as a waist harness and then when your back starts to tire, you can put the leg straps on and use it as a seat harness. Kind of a hybrid type of harness, the best of both worlds...
http://www.oceanrodeo.com/harness.php