Just got back from a ride with this item missing but the front plastic post, snapped of, still inside the grommet...
Bit of a mystery how it escaped from under my leg, maybe when standing.

Anywhere to reliably source one in the UK?

I saw someone on ebay in Oz who does whole fairing sets and I've dropped him a message but it'll be expensive with postage....

That stuff looks ok to me. Not as new genuine but seems fine. It cost me about £60 “entry fee” to bring a bike part in from oz. You can double check with post office etc. But aim for £60 ish with tax etc