I have a hayward Filter with a bump handle that I have to replace the Spider gasket in every couple of years because it will leak and the backwash hose will fill with dripping water. I replaced it this year and notice that the "seat" for laymans lack of the accurate part name, where the gasket sets in, one of the sides is broke off. Of course some leaking is occurring but not terrible. The question is, Can that part that the Spider gasket sits in be replaced or do I have to buy a whole new bump handle assembly? Also, as an aside, is it smarter just to replace the whole assembly since the filer is 21 yrs old? thanks