Condolences- sorry for your loss.
Sonically speaking Eudoxa is a good bit brigher than Oliv- but not harsh or twangy. I prefer Eudoxa, but my bass is rather dark on its own.
I would expect the same life span from either- but Pirastro's wound gut strings can be a bit of a crap shoot for longevity. I had a Eudoxa E that lasted for years, three or four I think- and I had an Oliv A that was good for about fifteen minutes before the windings started to separate!
Ya never can tell what they're gonna do till they do it!
I would think that an Evah should/could be a pretty close match in most regards- but I am passing on anecdotal information here, I've never tried them on any of my own instruments- but I have played them on other folk's basses.
If you liked the Oliv, I'd say get another one- all strings are gonna break some time!
Good luck with the search!