Your piece was produced by National Potteries Corporation, otherwise known as Napco,Established in 1938 in Bedford, Ohio. Height of popularity 50s & 60s. Napco used a wide array of marks paper labels feature various wording, such as: "A Napco Collection," "Napco originals by Giftware," "National Potteries Co., Cleveland, OH, Made in Japan," and "Napcoware, Import Japan."
I would say your piece is a pitcher value about $7.00 But what a wonderful piece full of memories for you!!