We were fortunate to be able to replace ours by contacting a local small business owner that cuts custom size foam cushions. We did a footprint of the shape and size of the cushions, and he took it from there. He has the machinery to cut that thicker foam where it creates a smooth finish along the edge.
We then had a local seamstress make covers to go over the cushions, and voila! Or if you can do the sewing part, you can make your own covers - but, I know I couldn't. They turned out perfect. Not sure if you can find a company around you that can custom cut foam pads or cushions, but that may be your first part to look into.
Since it's just the two of us in our trillium
we found suggestions here to make the bunk bed side into our permanent "dinette" and the dinette side into our permanent bed (still can take that side apart if we want to. So, the picture you see below is of our dinette with the cushions we had made. Nothing fancy, but they work.
Hope you can find someone that can help you out in your area!