I see what's going on. I have the Majority Greek text.
(Ephesians 2:7) [...hina endeiksetai en tois aiosin tois eperchomenois [ton hyperballonta plouton] tes charitos. (that he might show in the ages that are coming the surprassing riches of his grace).]
You must be using the Critical Text.
In any event there is no need to search for an antecedent in :7, since the verb phrase is natural and immediate. Further, all the English translations have "that" not "those/these" which would be required in English if "riches" (plural) were the antecendent.
But God, who is rich (πλουσιος) in mercy, because of His great love with which He loved us, even when we were dead in trespasses, made us alive together with Christ (by grace you have been saved) and raised us up together and made us sit together in the heavenly places in Christ Jesus, that in the ages to come He might show the exceeding richness (το υπερβαλλον πλουτος) of His grace in His kindness toward us in Christ Jesus (for by grace you have been saved through faith) and that [exceeding richness of His grace] is the gift of God, not of yourselves, not of works, lest anyone should boast. For we are His workmanship, created in Christ Jesus for good works, which God prepared beforehand that we should walk in them.Funny how this keeps mysteriously getting scrubbed from FR on Google searches over the past ten years or so while posts about Monica and the cigar are preserved.