Outside thermometer available?

I have a 99 Blazer LS and it has an outside thermometer which is an option I really like. I'm shopping for a used Equinox, 06-07 or so, and I am not finding vehicles with the outside temp option. Silly me, I thought that because my plain-jane 99 Blazer had it, all vehicles would have it by now... apparently not. What 'option group' is it part of and why am I having such a hard time finding it (on any vehicle for that matter)?

Thanks

your looking for a DF5 RPO code for your temp sensor....Good luck