Brake caliper Pistons

Hi
I am planing on refreshing my brakes and things this Christmas holiday so have been buying parts over the past two months.
Any way I started going through all the bits to make sure I had everything I needed and just noticed the pistons for the front brake caliper are plastic (can't  spell the correct name for the material) not steel like the originals.

So my stupid question for the moment is should I bother with them or just buy some stainless ones?

Thanks

Andy

Buy some stock ones, same brake is used for the XR250/XR400 if that helps your search

Thanks the site I got the front had pictures of the Pistons which showed them as steel ones and the rear kit I got is steel and it came from the same vendor.

Oh well next time look at the item when I arrives not two months later