The Topps Chewing Gum Company was founded in 1938, and from 1951, began to sell baseball cards that become its specialty. But the company continued to produce candies, and also some toys. Here is a Topps nose flute, found on The Topps Archives blog. According to the keeper of this blog and Wikipedia, the flute can be dated "after 1965", since the header card mentions Duryea as location for the company.
This nose flute clearly is a Humanatone, although I don't think it is stamped with this brand, which was still owned by the Fred Gretsch Mfg. Co. at this time (I cannot read what written on the flute itself...). However, it looks of a much better fabrication than the contemporary (end of the 60s) spin-off "Hum-a-tune" and its branded version Bullwinkle's Hum-a-Tune (1969), which were produced in Hong-Kong.
The Topps nose flute presents 2 features from the Humanatone that do not appear on the Hum-a-Tune : the small "true tremolo" hole on the right wing, and the lip-rest heel at the bottom (as did the late Gretsch Humanatones). The (yellow) plastic of this Topps looks more like the new Humanatones (consistent and not marbled).
I guess I can read on the header: « ©TOPPS CHEWING GUM, INC. / DURYEA, PA. 18642 / MADE & PRTD. IN U.S.A. » and I suppose this model was a "real Humanatone" by Gretsch (or already by Grover ?), but specially branded for the Topps Co. A physical examination would be necessary to be certain.
This blog is dedicated to the sublime instruments called nose flutes and which produce the most divine sound ever. We have chosen to discard all the native models from S. Pacific and Asia, for they need fingering to be played. We'll concentrate on "buccal cavity driven" nose flutes : the well patented and trademarked metal or plastic ones, plus, by a condemnable indulgence, some wooden craft or home-made productions.