As far as I know, the Duratone finish was Arrco's response to USPC's Cel-U-Tone finish used on the Congress decks. If I had to guess, they're from some period between 1950 and 1980, but that's strictly a guess. Trade value isn't as high for Pinochle decks as compared to Poker and Bridge decks.
Do a keyword search on eBay for "vintage pinochle" and see what comes up. It'll give you a rough ballpark of what those might be worth. But I don't think anyone here's going to have more info than that. Most of our vintage collectors stick to USPC decks like Bikes, Bees and the assorted special issues like the WW2-era Uncle Sam deck, etc. You'd need to find a more vintage-focused forum.