A few years ago, I acquired 3 pairs of Sulka pjs from a very rich family's estate--you should have seen their home! I believe that they were circa 1940s (belted top orange pair with button on wide waistband) and 1950s (other 2 pairs, with drawstring waists). The silver gray pair from the 1950s is dated 1953 on the label, luckily enough! All 3 pairs had stripes on the sides of the pant to match the trim on the pj top: a wide stripe similar to tuxedo pants on the orange pjs and a narrow stripe, like piping, on the silver grey and off-white pjs.
I'll attach the photos and labels below, for reference. Feel free to use the labels for the LR, if these are different from the ones we already have?