Ok it's here! The light in the room with good mirrors had gone so I took it down to the charity shops where the strip lighting is effective if pitiless.
It's essentially just what I've been looking for all this time: a waxed cotton trench coat with hood. I love the Humphrey Bogart goes to Sandringham vibe (although I'm sure Bogart would have had far too much class). Love, love love the waxed cotton, to which photos don't do justice. It!s so much nicer than technical fabrics and it ages well too. It's also made in Britain which is another tick for me.
It's the most generous size 8 I've ever seen - arguably a bit too roomy but means I can bulk up underneath.
Speaking of which, considering the price, I'm a bit miffed they've not made it compatible with the Barbour zip-in quilted lining. Not that I can afford one at the moment and will almost certainly substitute with a Uniqlo gilet. But it feels mean spirited.
Think my main issue is that it doesn't work belted up as well as I'd hoped. Looks a bit stiff and bulky, which I imagine is partly the fabric and partly the straight up and down shape. The fabric will soften up but the shape won't.
So although I really do love it, I'm still going to think for a few days as it's £200 over budget and will mean no more fun for several months.