I have asked this question before and all I ever Got was stupid comments about MOW, or pay a hefty price for the scuba harness. I'll tell you what I did. I tried several options but ended up settling on a basic Camel-Pack. These things are padded all around and are extremely conformable. I don't have a picture of my harness, but basically I removed the water pack, and cut the outer canvas off so it was just shoulder straps and back. Then I sewed straps to the shoulders and attached an aluminum rod, I bought from lowes and bent myself, across the bottom with two screws, nuts and washers. Sewed my scuba belt to the bottom of the harness on each side. I have a MOW jet pack and if you didn't know, those things are over 15lbs. I can wear it all day no problem. This picture is the closest I can find of what I used.
[ATTACH=full]166465[/ATTACH]