Think about this - how many 1 ton Chevy trucks from this era have you seen? Ok, then how many were 2wd? For me, like 95% of the ones I have seen ar 2wd. There seems to be just less 4wd ones, which are the only donors for our trucks.
Then realize that people have known for a long time that a Dana 60 front a 1 ton will bolt right in on your 1/2 ton truck or blazer. So these things were never just sitting around in a pile, gathering dust.
So yes, it's supply and demand.
When I first got in 4 wheeling a few years ago, no one I knew would consider paying $1000 for a Dana 60. But now they are just that much more difficult to come buy and that price is not an outrageous one.
-- Mike