As per the Golden Age Star-Spangled Kid/Skyman (Sylvester Pemberton) Appreciation (2019) thread, first appearance was in a preview/promotion in Action Comics #40 (September 1941):
Stripesy then went on to share a feature with the original Star-Spangled Kid (Pemberton) in Star Spangled Comics and was a member of the Golden Age Seven Soldiers of Victory.
From Who's Who: The Definitive Directory of the DC Universe Vol. XXII (December 1986):
Many years later, he partnered with a new Star-Spangled Kid (his step-daughter) as S.T.R.I.P.E.
from DCU Heroes Secret Files #1 (February 1999)