@DanScarb: As the One Connect box comes packaged with your TV, you will be able to provide the serial number of the TV itself when arranging an engineer's inspection. For clarity, this can be found on the sticker on the back of the TV.
Typically, One Connect boxes are only compatible with the TV they came packaged with, so it is not likely that the replacement you've mentioned will work as expected. With this in mind I recommend arranging an inspection, to a void any potential compatibility issues.
