And indeed although the part number for the handles are different the part numbers for the gaskets are the same. So the gasket ment for an Alpine door handle will fit the door handles from a Rapier.
I usually use a scrap of old cycle inner tube. fix the handle on top of the rubber trimmed from an inner tube, then VERY carefully trim around the handle with a sharp knife, stretching the rubber slightly so the cut edge hides under the handle.