Closed-cell packing foam (Greenlake)

I'm working on an art project, and could use some 1/8" thick foam padding/sheet. The sample I have came out of a package shipped to me. Like some Amazon or similar envelope insert.

Color: doesn't matter.
Thickness: 1/8"
Texture: not crumbly or really easily torn.

My goal is to save resources by reusing something that might regularly be considered garbage. I'm looking for material close by in my general area.

Thanks for reading this!

       
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