I know they aren't in the Purrs shop but I find the Catac pillows the best . Even though I have bought new ones, Alice still has one from over 2 years ago and although it is yukky green when she licks it, it is still intact. I just give them a squeeze to get the smell going again. They are made from really strong cotton - only £2 each
(I sometimes top up a VetUK order with a couple if I am under the limit
They are nice & flat for posting as well