it's had to tell from a photo, however, one indication to look for is "fat" feel to a scotsbluff or a red river knife or a cody knife. I'm not shure what the difference is between the two knife forms. Any artifact from the cody culture is always special.
This is NOT a positive ID attempt,,,,,I just offer this as if it was my own.
Comparing it closely to the several examples of Red River shown in the OvrSt book...they all have a hint of barbs whereas your find has the REVERSE, ie:
the point edges actually go IN from the square base, sort of like a reworked favorite hunting point or even a perforator.
Wow, that is a beautiful peice! Im not an expert by any means, but I don't think its a red river knife. It looks like it has a distinct flute, and red river knives were basically reworked scottsbluffs. I was thinking Meserve at first, but it doesn't have the concave base that is typical of that point. Is the basal area ground? It looks like some type of resharpened paleo point. Either way, its a great find...congrats