I picked this up at an estate auction a couple of months ago.
Diameter is 50mm. Length is approximately 347.5mm.
Markings on the “nose” are: i kpp 37 centered in the middle. There is a number 13 inside a circle on the top right and some unidentifiable figure on the top left side.
I am not sure the painted “tail fin” and “nose” are correct, but it is nicely done and appears to be about the same age as the rest of the item. There is some type of corrosion on the main body, which I believe is aluminum.
I can provide more photos, if needed.