Material under Arcade Sticks

Does anyone know what the material sometimes used on the base of various arcade sticks is called or where I can get it?

Images in case it’s not clear what I’m asking about:

Self-adhesive sponge neoprene… the ones in the Mad Catz TE2 fightsticks are 1/8" thick. You can find them on Amazon and eBay.

Looks like EVA foam on the Mad Catz sticks. It’s not great, but cheap.

I use PU foam on my Panzer stick. It’s durable and you can get it different firmness.

edit: new link. this has an adhesive backing.