Under plates for flower pots (Kemptown BN2)

Hi there,
I'm helping an elderly housebound relative. They're looking for some under plates to put under flower pots (indoors). Can be plastic or terracotta/ceramic but would prefer something that is made for that purpose rather than just using an old lid, as it doesn't look good. Doesn't have to look exactly the same as the screenshot.
Thanks in advance.