I think your Gateman is from 1969.
I'm no expert but the 6-2145 number got me thinking. It's not the 45N or the 145 but 6-2145. Post war by 1 year. I don't know about your piece but it's common knowledge that the man is huge. and with the 45n or the 145 there's a light that shines from the outside floor giving the effect the lantern is lit. The 45N I think was partly prewar carried over to postwar.