i wouldn't say tribal weapons, but rather improvised weapons in general. like a spring + tube + railroadspike-ish piece of metal = makeshift harpoon. crossbows are pretty powerful and easy to make as well.
some people tell me bullets could easily be crafted in a post-apoc environment though, but i'm not convinced. also, firearms tend to degrade rapidly (or at least some internal parts), which means there would have to be quite a few skilled gunsmiths to maintain those in working condition.
for me a truly post-apoc wanderer would walk around with quite a few different weapons. a simple knife, a multipurpose axe (for melee, wood cutting,...), a low tech weapon with ammo that can be reused or easily crafted (crossbow, springgun,...) and perhaps a fairly simple firearm (double barreled shotgun, bolt/lever-action rifle, revolver, LMR...). only in fairly rare cases one would posses a higher tier firearm (semi-auto pistol, SMG, AR, MG) and most of those would be in pretty shabby state.
still, it depends how badly civilisation would've been hit, of course.