Answer:
My wife and I found an antique cabinet that will be perfect in our dining room. The woman at the antique shop assured us that it's a rare collector's item.
Step-by-step explanation:
The use of pronouns depends on the nouns used in the sentence or adjoining sentence. This means that the pronouns to be used depending on the nouns present in the sentence.
In the given sentence, assuming that the words in bold are "my wife and I", we can safely say that the pronoun to be used in the black will be "us".
This will give the full sentence as-
My wife and I found an antique cabinet that will be perfect in our dining room. The woman at the antique shop assured us that it's a rare collector's item.
Or
In case the bolded word is just "my wife", then the pronoun in the black will be "her", then it becomes
My wife and I found an antique cabinet that will be perfect in our dining room. The woman at the antique shop assured her that it's a rare collector's item.
Or
If the bolded word is just "I", then the pronoun in the black will be "me"-
My wife and I found an antique cabinet that will be perfect in our dining room. The woman at the antique shop assured me that it's a rare collector's item.