CPT for intercostobrachial block ?

I can't find much guidance on how to code an intercostobrachial nerve block. I've seen 64420 which is for "intercostal," and 64450 (other peripheral nerve or branch). Descriptions of intercostal blocks say they are for surgery around the chest and abdominal wall, and the injection is done in the area of the ribs. Intercostobrachial blocks are done on the inner arm near the armpit and are used for upper arm surgery.

I'm leaning towards 64450 since the indications and the location for...

CPT for intercostobrachial block ?