US WWII M1 Steel Helmet & Liner, Swivel Bale, Red Stripe Top

Original period manufacture. Front seam, reflective edge helmet with swivel bales and original sewn light OD chinstraps with steel fittings. The lot number inside the shell looks to be 38C.  On the top of the helmet, is a hand painted red stripe, and on the front, a stenciled REP 1. No idea as to the significance. Typical high pressure liner by Westinghouse with light OD webbing and original sweatband. The liner exhibits considerable wear, as does the exterior paint finish. On each side of  the liner are hand painted red squares with two diagonal black stripes; again, no idea as to meaning.