Not sure if you have time for this, but I have multiple copies of my Bank of America debit/credit cards. If you lose a card they issue a new one with a different number, but if one is worn out then they issue a new one with the same number. Once I learned of this I used it proactively to get two cards with the same number for all my accounts so I can leave one hidden in my car in case I leave my wallet at home.

YMMV with other issuers, however, so make sure to ask what they do when a card is replaced for wear and tear.

Then just give your partner the card!