I currently have neoprene? washers on mine.
Give skifast1 a PM if you're looking for the washers, he bought a bunch of them in bulk to make his tun and he's been selling them for $1 each. I just got mine (3) from him this week and haven't had time yet to swap them out. I'm not sure if I got the last ones or not, but if he still has some that saves you time from having to do it over or buying in bulk.