Online stores like Amazon or eBay have plenty of those (sometimes called also gaskets). The seal tends to become brown over time as the silicone absorbs some qu

Online stores like Amazon or eBay have plenty of those (sometimes called also gaskets). The seal tends to become brown over time as the silicone absorbs some quantity of coffe in the process, but that does not affect the taste of coffee and the seal keeps doing its job impeccably (up until ~6 yrs at least, ymmv).