You are right; part of the fun is the hunt to fill out the entire collection of eight. I have looked for about 5 years for this card. I, too, saw the one on CV Treasures but it was long gone. Also, about a month ago, it showed up on Ebay. But, it was pretty banged up and I decided to not buy it but continue to look.
I remember some years ago I bought 7 Goodbye Mr. Chips cards on Heritage. The Title card was missing. I was so excited to find the Title card at Cinevent to complete the set. I went to Cinevent because I heard it was a huge film convention (I also collect film). The convention did have some film, but I honestly think it was more of a movie poster/lobby card convention than anything else.
Does anyone go to Cinevent to shop for posters or lobby cards?