WW2 Era - Home Front / Civilian Helmet

WW2 Era British pattern helmet, MKII Grade 2C, (Triangle 3 holes on brim). Made of mild steel, not fit for combat use, only for home front or civilian use. Liner marked: 7 1/4 TTC II 1940 ( Size: 7 1/4, liner made by: Teddy Toy Co. Ltd. Dagenham 1939 - 43. Mark 2  & date) Helmet seems to have original paint work, Olive Green outside and Field Grey inside. Chinstrap intact, but has come apart at one of the springs, could be repaired. Liner missing securing lace. 5 Tongue liner. Chinstrap lugs are square and riveted. Markings on helmet, all seem to be below the one chinstrap lug and at the three holes: either: USO / JSO / US6 / JS6, also a 1 and 19? See 7th image.