Mk-3 speedo drive

Hi I noticed the round pointy rear end of my speedometer drive is missing along with the gear. Does any one have one for sale? Its for the rear disc brake Norton / Triumphs and mounts on the left side hanging down . I have been trying to find a good reference for identifing the various smith speedo drives. different vendors list a different smiths # for Norton PN 06-5540, which I think is the right Norton PN? Anyone out there have a good listing of what's what??

A replacement 06-5540 speedo drive gearbox should be available from any good Norton parts supplier.

The same unit was also used for the Triumph Trident T160 (rear disc brake - L/H speedo drive gearbox) so an identical part could be offered under the Triumph part number 60-4403 although these modern replacement units are I think no longer made by Smiths and do not last as well, but still carry the Smiths number stamped on the inner ring, so if you look on the inside face of the speedo gearbox I think you should find the Smiths number BG5330/164.
What alternative numbered part have you been offered? Any other Commando drive gearboxes offered under a different Norton part number could be earlier right-hand side (drum brake) units.