If you are referring to the "spit pad," it isn't anything special and should last the life of the machine. I have had them pop out somehow, but just stuck them right back in place without issue. Mine are all crusty and black with plasticized ink all over them and the printer still works and cleans fine. If yours is gone, and the vendor charges an exorbitant amount, maybe you could cut a small piece of sponge the same dimension and stick it in there.
Good luck!