Something Dave said made me realise that a bit of gentle persuasion via a hacksaw blade (saw in two through horizontal bearing surface) would do the trick, after all I will fit new bushes when the swing arm has been powder coated.
I did think about sourcing a split internally tapered collet and tapered bar (which is what I guess the Honda service tool will look like) but then I realised I was going too far and decided to resort to the old bike fixers mantra 'if you cant do it properly, bodge it'!
Bushes £8.50 each from David Silver. David Silver have revamped their web site and it's much easier to find parts now.
Andy
PS - Dave, checked photos today and have not got any showing bar end mirrors. I will take a couple and post as promissed.