Vessels of Wrath = Jews (under the old covenant)
Vessels of Mercy = Gentiles (grafted into the new covenant)
Paul is not therefore talking about the eternal destinies of these two peoples obviously, as Paul himself was a Jew saved by Jesus. But about the fates of the two peoples; - Judaism would die out to be replaced by Gentle-grafted Christianity.
However, I feel that there are, some basic problems with such a view. Verse 24 reads (as an immediate follow on from v. 23) - even us, whom he also called, not only from the Jews but also from the Gentles? Paul notes that both Gentiles and Jews are in the category 'vessels of mercy.'
Therefore, the vessels of wrath and vessels of mercy cannot be Jews and Gentiles respectively, as both Gentiles and Jews are identified as vessels of mercy. And we may infer from this with working parallels that both groups are also found in vessels of wrath.