Large back of sofa cushions (Aylesbury HP20)

Hi 👋 slightly random request but I'm looking for two large cushions that would go on the back of a sofa usually to lean back on. I'm looking for it for my sofa as it only ever came with normal cushions and they're no good for my back. I've included a photo of the type of cushions I'm after. Hoping someone is getting rid of a sofa and I can nab the cushions thanks !