Have you tried ordering off american websites? I think most of them will ship overseas. At least I know backcountry.com and all it's steepandcheap.com affiliates will (cleansnipe.com has them all, but the cycling specific ones are bonktown.com & chainlove.com) Certain brands they can't ship out of the US, but I don't think Marmot is one of them. I know arc'teryx is.

I'm not too familiar with the brandnames available in the UK, in fact most of my Scottish relatives have me stuff and mail it over to them. Can you get 66 north? It's an icelandic brand.

The other thing to do is maybe hit a TK Maxx and hope you luck out finding something? Do they have those in London? There's a couple around Glasgow that I've gone to with my cousins, and they're basically a TJ maxx. I have seen 66 north in them.

You should also be able to get Mammut over in the UK, I think they're a Swiss brand (?) - I mentioned the mammut ultimate hoody unzips all the way for pitzips, I've also got the mammut stratus hybrid which has a windproof somewhat insulated front panel, and the rest isn't.

I'll look if I can figure out what model the rei merino wool/windproof jacket is - but I think it was billed as a nordic skiing jacket and not a cycling specific jacket. I tend to repurpose my ski gear for cycling when needed.

Event is much more breathable than goretex if you can find it.

If you really can't find something over there, and you can find something on an american website, I can maybe get it here and ship it over to you. (I have to support everyone's wool habit, of course)

I think they do sell icebreaker over there - Have you tried the raven or the allstar jacket? The weaves on them are fairly tight and pretty close to windproof. (Okay, I will admit I haven't bought icebreaker new in a while, so the model names might have changed) But basicaly their thicker full zip wool jackets. Pairing one of those with a lightweight wind shell might work for you?