Using my resources to look into your inquiry, I was able to find comparable sales that give your posters a current secondary market value of $30 - $40 USD a piece at auction or in a private sale.
I hope this answers your question! If you are satisfied with my answer, please click “ACCEPT” so JustAnswer will credit me for my time & work (at no further cost to you). Thanks!
Alan C. Ransdell, ISA AM, AOA AM, CA