Replace inside handle

Thanks for posting. Was the thumb lever placed closer to the bottom of the handle? If so, the 82-090 or 82-089 will work for you, depending on the finish you want. If the lever was perfectly centered between the mounting holes though, go with the 82-030. 

Note that a damaged thumb lever can indicate that the mortise lock in the door was broken and should be replaced. To test this, remove the handle set from the door and try manually 'throwing' the lock with a slotted screwdriver. If it doesn't budge, then you know the mortise lock must be replaced. See the 82-226.