John Candy wears a Casio W-34 digital watch in the movie Planes, Trains and Automobiles (1987).
The watch can be seen when John Candy's character tries to pay for a hotel room with the watch. His friend, played by Steve Martin, owns a gold Piaget watch.
The Casio W-34 is very similar to the Casio A159W-N1DF digital watch, which is still available today, but it has a slightly different face: a lighter blue Water Resist bar, and no red WR text among other things.
The Casio W-34 can still be found on eBay although it is rare.
It's easier to get a Casio A159W-N1DF on Amazon.com or find that one on eBay for anywhere between $21 - $40.
We have spotted some gold versions of the Casio A159WA in other movies, see them here.
Other similar watches are the Casio A158WA (also seen in films) and the Casio A168WA (seen in Squid Game for example).
With thanks to Digital Watches