I found a french sweet iron loose ring in the english bits on State Line Tack for a good price, but you're right, it seems to be that sweet iron is more prominent in the western world. At this point, me and my trainer are leaning towards the one that's all sweet iron.
I used a french link eggbutt last year in Intro level with Jack, only because it was my trainer's preference and I was only leasing him. I've always preferred loose rings. You just have to order a size up to prevent pinching.
Cinnamon Whiskey 11 y/o 15hh Chestnut AQHA mare, 2'6 Jumpers