I didn’t notice at first, the article itself links to a seemingly easy way of making a DIY adapter:

http://damntechnology.blogspot.com/2009/02/hacking-dvi-cable-to-build-adc-to-dvi.html

If the demand is low enough to not even bother stocking them anymore, it would seem like someone could offer to sell them on Etsy or something, doesn’t seem to require much much tooling.