Might be time to use your computer to catalog what you have. A couple years ago I was searching for an extinct character and found there are also sellers and collectors of such stuff. You could have fun completing the set.
I'm moving to Tucson, soon, and they have a store called "Bookman's" that sells used and rare books, so I think I will wait and see what they have.
I may email them and have them search while I am in the moving process, so I can get it as soon as I am there. In the meantime, I'll see what is available online so I can give them all the titles I want them to search for.
Thanks for the idea.