The first thing to remember is that the M43 is an enigmatic off-shoot of the GI MK II. The original M43 handles, as in vintage, were around 4 1/4" IIRC. I don't have my data with me at the moment. The blade on them, as well at the MK II, were both around 12". The MK II handles added about a 1/2". M43 handles were too short to be ideal and the MK II seemed better suited for larger hands, though the M43 handles like a dream.
In contrast, my HI M43 Model had 6" wood handle slabs, a 1/2" bolster, and a 13" blade. It is a great khukuri design, just nothing like the original.
So, to answer your question, a period MK II/M43 would have a handle of 4-4 3/4", a blade of 12", an OAL of 17.5", and a weight of 22-25 oz. this is just from my samples and from reading about others. There were period MK. II made heavier, up to 26-27 oz, but they seem later WWII production and it seems handling qualities drop off at that point.
Please don't take this as bashing HI's current M43. It's a totally different khukuri than the vintage or some of the original HI models. People love them and it's one of the best HD choppers made. For a big blade, they handle very well.