Gyrojet - can’t help too much, but I can tell you that Vic’s for Guns was very active in the surplus ammunition business, probably in the 1950s or so (it was pre-ZIP Code, according to the box label). I remember them from a long time ago, but not positive of the dating.
They packed all sorts of ammunition in those same boxes. I have one for 8mm Mauser ammunition. They were not too careful of what got into the boxes. My 8m/m Mauser box had one round of 7m/m Mauser in it, and although supposedly ball ammunition, had a number of S.m.K.L’spur-v rounds in it as well. In fact, a couple of them were quite corroded and should have been discarded by Vics even if they were ball rounds.
If I can find out more, I will post it on this thread.