Foam for Sofa cushion (West Malling)

Hello ALL,
Photo attached is for reference.
I was wondering if someone has some big block of medium foam (NO memory foam) for sofa bottom cushion (like the one in the pic). Thick around 10 to 15 cm, would do.
Maybe from an old sofa or chair? as long is not 'unsanitary' for the purpose I have to use it 😊

If you have it, I would love to collect. If you don't, you have a nice day too 😁
Thank you very much for reading
Marco