So 4 of them go into one 3* weapon
With the leftover 1 or 2, there are basically two real options:
1. Use as skill leveling fodder as mentioned
2. Hold onto it/them for a long time; exchange for more copies in the shop that gets added in December. This costs 2 orichalcum per copy, IIRC. And orichalcum is usually preferred to be saved for final limit breaks.

With just the 5th copy? That's asking for 6 orichalcum to max that, so that requires really, really loving the skill(s) on it. I personally don't value Pride that highly, but maybe you do.
With 6 copies? Then that's 4 more orichalcum to max that. Then that's getting into the area of really liking this particular weapon combined with not really having other stuff that you want to carry out the final limit break for.
Final limit breaks require 2, 3, or 5 orichalcum, depending on how the weapon was acquired. Advent SSRs need 2, union event and SSR kamihime weapons need 3, and the draconic eye exchange weapons need 5. (plus a bunch of other stuff)

Once the Guild Order type events start up in August, we have the opportunity to pick up 0 to 5 orichalcum every two weeks. I don't know how strong you are, so I don't know how valuable/rare ori would be for you.

I'm in a similar boat with other weapons. I've got 7 copies of the sword from Amphisbaena. I like dual skills (especially with both assault and defender), so 2 ori to max a second one is an easy decision. I've got 5 copies of the sword from St. Nicholas. That one's a lot harder for me to decide. I'll have to see what my ori collection rate is.