Sounds familiar!
https://m.imdb.com/title/tt0734679/
The Trade-Ins (20 Apr. 1962)
TV Episode of The Twilight Zone
The Trade-Ins (1962)
An elderly couple shop for younger replacement bodies, then resort to desperate measures to cover the cost.
“An elderly couple shop for younger replacement bodies, then resort to desperate measures to cover the cost.”
i vaguely remember that this was a ripoff of the basic idea of “Gift of the Magi” ...