No idea. I did find that WDC are still making a variant of the 16-bit successor to the 6502, so I hadn't considered that the tech might not still be around for the earlier generation.

It was only very recently that they stopped making Z80 cores for embeddable use, so if that tech was mothballed rather than thrown out it, theoretically it wouldn't take long to spin all that back up again.

That "theoretically" might just be an uninformed dream though.