A lot of these you can look up on
ebay, I went to the United States category and searched for "the best of the decade" and found this;
https://www.ebay.com/sch/i.html?_od...e&_sacat=261Using the left hand column I looked at the "sold" items to get a real value.
I'm not into FDCs but they are usually worth 25c apiece of less for modern stuff.
I'd say the everything together is worth about $100 - $200. Hope this helps.