Cork padding replacement for chin rest

Howdy folks:

The cork padding on my favorite chin rest is wearing out. My luthier said a DIY solution is pretty easy but there is just a hair in the soup. Where do you find the cork sheets (2 mm thickness) to make the replacement paddings? The cork sheets I could find on-line are for home improvement and they are huge! Where can I find them in "hobby portions"?

Thanks in advance.