Unfortunate is right.
I'm told there's a 'whole lot' of them sitting in a warehouse. These are castings fully machined ready to assemble etc.
It's realy a long story.
I think there was a SNAFU with the rocker arms as the orginal (1946) ones used 41 Buick (straight 8) units. Custom replacements were "in the works" when things stopped.
Like Drew said though; "don't expect them anytime soon".....