Thanks, @sns , I would like this amp to last longer than I do, if that is possible.
I just got done looking on partsconnexion, & this may not be as easy as I was thinking it would be (finding one with the specs I want). I'll do a search on the others you mentioned--Mouser, Allied.
If worst comes to worst, I guess I can email Cary & try to buy four of them there. Back in the 90's I bought a "power-bank kit" (added filter caps and an umbilical cord to attach them with) for another Cary amp I had, and I am going to look, but I am thinking that they were the same value. Cary's prices for signal caps are crazy, though, and I suspect they would be for filter caps also.
Regardless, thanks, & I'll look at those other places you listed.