I know the old Curtis Keyer chips (8043, 8044, 8044ABM) are long out of production.

Out of curiousity, is there a modern day equivalent of this chip available from anywhere?

...yes, I know Curtis sold the line out to MFJ when the company went away, and that for a time they had a chip called the 8045ABM; but I can't find any mention of it on their site, so it to may have gone away too...