Bose replacement speaker chassis?

[Matt B]

Many of us have rebuilt their Bose head unit, cdm and amps. But considering the age of our beasts I was wondering if there are quality replacements for the Bose speaker chassis themselves.
All the materials suffer from aging, magnets lose their strength, etc.

So, is there an equivalent in the market to replace worn Bose speaker chassis with a substitute that matches all oem parameters?

To make it clear: I don't intend to swap out the Bose system or plug in ANYTHING that physically fits the speaker housing. I'm looking to refresh the system with new but OEM like speakers.

Any ideas or experience?