I can take more measurements of those parts when I’m back in NYC tomorrow night. I’ll send them to you and you can own sending them since I don’t want to create too much confusion or noise for themAh no worries. And off the top of my head, perhaps the height and width of the pockets. As well as the length of the arm triangles. These things tend to be off by considerable margins. Your size 18 jacket is good to base things off of for their size Small jacket. Id measure the pockets from my vest but it is currently in Pakistan for Magnoli Clothiers.