I happily resell you Intel processors at a 10x markup but you get a ten year warranty that I'll replace your processor with a new one of no worse specs, if similar vulnerabilities get discovered.
Details to be negotiated.
(More seriously: you don't need a new manufacturer. Someone else can do the warranty at a price.
That's actually what eg Apple Care: if a part inside your device catches on fire, Apple will replace it, even though they did not necessarily manufacture that part.
I have no clue whether their particular policy covers the vulnerabilities we are talking about. But you can easily imagine a variant of such an insurance policy that does.)