That is certainly quite a pile of classic lead. That range had some really cool figures, some of which still get promoted into the land of 28mm giants for my games.
I cannot add any real advice to GurKhan's sage "nobody really knows" answer. I agree the beaver skin hats are not so correct, but maybe these are "Mountain man tribes" (humor!).
Yeah the spears are going to turn into spaghetti on those. The good news is you might get away with just drilling the front hand, and then the back end can stay lead, and you can trim it.
As for length of sarissa and xyston, I took a stab at that awhile back:
link
Much more info is available. My guess is the majority of confusion comes from Arrian equating the xyston with the kontos of his day.
One thing for sure the xyston fighting style as described is much different than two handed kontos style.
Last time I looked we still don't know where the word xyston comes from. I just call them 'lances' in my gaming vernacular since in style and description they seem more like lances used by Bengal and Napoleonic cavalry. And they break (a lot).
But much of that goes against some sources.
Of course now we have instant access to this kind of primary source. The broad blade does seem to indicate sarissophoroi?
steps into the arena with two gladiators from 
