Sizing on Barbour Inverrary wool coat

[AppleButter]

I would be grateful if someone could let me know what the sizing is like on the green inverrary Greatcoat, I wear a 10-12 usually, and prefer an slightly oversized look. Perhaps oversized is not so ideal if you are on the short size.

If anyone could measure the underarm-to-underarm on a size 12, I would be grateful, but they are out of stock anyway., only the size 8 left in stock which is probably too small for me post-kids. Thanks very much for any info.

I have the xs in this coat. I’m a size 10 and it fits really well, but I couldn’t wear knitwear under it. That’s probably not very helpful sorry!

That is actually very helpful, because it means that the sizing is a bit bigger. The XS is size 8. So I probably do need a 12 If I want to wear another coat under it. I am wondering if I could get the 14 but it kight be massive.

Just had a quick look and House of Fraser have it in a 12.

Thank you too ticky, that is very kind of you to check :)
Finding it is one thing, The price is still massive though :( for 60 percent wool.