1) Am I the only numpty brained oaf in history who's damaged a wood rimmed wheel like this?
Nope. I gouged a deep scratch in mine about a year after I fitted it.
2) As I say it's blended in well and now not anywhere near as angry as it was but I want it sorted. It's a Moto lita obviously.
Does it mean sending it back to them or do we have a specialist in our midst who could help? Any idea on cost please? I've not a bloody clue.
Sounds to me like you've done a pretty good job already. It's just a bit of patina, something to mark the fact that you and your car have interacted, are building a relationship. As the years go by your car will accumulate others, it's inevitable if you are to use and enjoy the thing rather than wrapping it up in cotton wool.
You paid a lot of money for your car, much better that you relax, accept the inevitable wear and tear, and get the pleasure of owning it rather than keeping it nice for the next owner.