65 KAIC could very well be sized in excess of what is really needed. Such as standardizing on parts between related jobs, rules of thumb that are conservative for the size of the service, or rounding up to what was most readily available at the time it was built.
For any given device, the KAIC rating needs to meet one of the following in order to comply.
1. Meet or exceed the available fault current at that particular point in the circuit.
2. Be series-rated with an upstream overcurrent device on its line side (i.e. closer to the source of most of the fault current, which is usually the utility service). Breaker manufacturers have series rating charts that show a part number pattern of line side devices and a part number pattern of load side devices. There are also series ratings with given classes of fuses as the line side device and given part number patterns of load side breakers. It is a specific combination of devices that are tested together. Don't expect series ratings across multiple breaker brands.
3. Take credit for the impedance of the feeders between the service point and the point of the device in question, to determine how available fault current diminishes along the circuits. You'll need to know the wire size, conduit type (i.e. metal vs non-metal), length, number of parallel sets, conduit type, voltage and single vs 3-phase.
There is a fault current calculator spreadsheet available on this website that enables you to input the specs of a transformer and the specs of the service conductors, feeder, and branch circuit to determine the fault current at any given point. This does not include motor contribution fault current.