I have the Rivco risers on mine right now and they work well. I have a set of Thunderbird 1700 risers on the way to see how they look and feel. If you don't have any luck in the next week or so get in touch with me if you would be interested in the T-Bird risers. I am not sure how they compare to the OEM Rocket risers, do you have a Triumph part number for the OEM?
bob