Nat&Dot's Profile

That ceiling light is ridiculous - why does that light show up in every kind of apartment! You should get something that will hang below the duct. It would probably help create a separate space. Maybe you could make it a little nook - for reading, office, whatever.

Asbestos pipe wrap usually has a distinctive honeycomb profile, sort of like corrugated cardboard. You would usually find it on radiator pipes or something that needs insulating. That looks like a big pipe, not like a hot water supply.

There are some online sites where you can buy custom cut foam and the price varies depending on quality. Also, Joann's Fabric sells foam, though I'm not sure if they have single pieces large enough. Do you have a sewing machine?
My sewing skills are pretty limited but I made square cushions for a chair. I found that adding piping camoflauges my bad sewing! I just traced the old cushions, mine had rounded corners and I think it would have gone better if I had squared them off. I also used a non-geometric pattern so you can't tell if it's crooked. And velcro to make an envelope closure instead of a zipper. Good Luck!