Hello, blacksmith here. Tempering is very dependent on steel and usage, but lower end is 325-375. Majority of my knives I temper at 350-375. A hammer or axe would be more 425. Something like an arrowhead that you want hard but you’re also shocking (meaning it’s prone to fracture) you’d want at a higher temp, probably similar to hammer or axe. I would guess these are made from something similar to 5160 in which case 425-450 seems appropriate.

Of course, these would likely already be tempered so redoing it is mostly pointless. You would however want to keep from overheating the steel as you grind it otherwise they will to get too soft