I called Rivco. I was told that they have tried a couple of time (and once with a Triumph Dealer) to make the risers they have available for the Standard to fit a Roadster and they just will not.
Or hang on, I recall seeing one of the fellows on r3owners.se installing some more off the wall specimens. Had to go look it up and wound up with http://www.roxspeedfx.com/
They have nothing specific for the Roadster, but possibly some that are for other 1 inch bars might get the job done.
I finally had time to try the ROX risers as suggested earlier. After re-routing the cables and front brake hydraulic line to the rear of the Tripel tree instead of the stock position that they all are in (front) of the triple tree. And trimming the side fram panels a bit to allow the cables some free movement the ROX risers worked great. I did have to plane the riser caps down bit to allow them to seat not the OEM bases flat. The RO users have a small lip that fit their risers. Since the ROX riser caps are required to be used no the OEM bases and the OEM base is required to be used on top of the risers ( to allow the speedo and tach to mount) they required some milling on a flat file to remove the lips that they are manufactured with. No big problem. Works great.