Give the special lady a special ring, a dimein ring...
Our dime-in-ring is a great way for the hard-of-hearing to save money; You know she asked for a "diamond ring", but she doesn't know that you know. She will have to give you the benefit of the doubt when you give her our lovely "Dime in Ring".
For best effect, find an old Zale's box at a yard sale and present it in that. One size fits all, because by my calculations, having it resized would cost about 20 times what we asking for one of these gag rings.
THE USUAL DISCLAIMERS APPLY; Esp. not for children under 3; choking hazard. This is a novelty/gag gift meant for adults. Childish adults to be sure, but adults.