The 24" & 30" reel mower attachments were basically the same, except that the hitches were different for the different years/tractors.
It is possible that it's the correct model number on the attachment, but it will definitely not fit a Ride-A-Matic or Versa-Matic in its present configuration. .....That style hitch fit the Bolens PowerHo walking tractor.
Early Ride-A-Matics and VersaMatics shared a different style hitch than the PowerHo's.
Later Ride-A-Matics used an even different style hitch.
The hitch on the reel mower attachment could be easily changed from the PowerHo-style to the VersaMatic-style by unbolting the hitch, and bolting on the other style.
The price seems fair, as the condition is very good!