Cosplay Help/Recommendations

I am currently working on a Hanji Zoe and Sasha Braus cosplays from Attack on Titan for a convention I plan to go to in May, but I am having trouble finding a imbracatura that will fit me. I have a larger bust, D cup size, and I am on the heavier side, so I was already doomed from the start. I was wondering if any cosplayers on this page could help me out. I want to either find one, o make my own, but I need help. What websites would te recommend checking besides Amazon, Ebay, and Wish? How would te go about making them? I would go without, but the problem is I am making the 3D Maneuver Gear, so I kind of need the harness.