I've been working on a DIY repair kit for 4-speed gear selector rod tips (the plastic bits that get worn and break off, leaving you with a sloppy gear lever even when everything else has been sorted) which I am currently durability testing on our syncro before going on sale.
I've applied the same principles to the 5-speed lever and have devised this:

which is infinitely preferable to this:

C/w comprehensive instructions, but fitting is well within anyone's abilities. All you need is patience, mole grips (or a small vice) and some epoxy glue.
The next piece of the puzzle will be remaking the guide blocks (shown here badly worn by a damaged lever fork):

This process will be made a lot easier with access to a factory production drawing
