In reply to Si dH:
Thanks for the responses all. I've emailed Rab.
I don't want to do a very obvious bodge-job, I'd really like to make the repair as inconspicuous as possible as I like to wear it out and about and to work when its cold (to the extent that I still have an old, tatty & dirty Neutrino Endurance that I still wear to the crag so that I can just chuck it around - the plan was to swap them when that one finally dies, and now it looks like the new one is dying first having had very little abuse)