I am answering this, as if it was being asked of me, as I am approximately 50 and making a wedding for my first at this time.
I don’t need anything, and I would not want to be young couple to spend money on buying me a gift, but showing hakarat hatov is priceless.
A heartfelt note/picture maybe framed.
Maybe send flowers with a note the Shabbos after 7brachot.
