Refunding 1/XX of an item

Currently, the refund feature only shows the total paid for a group of an item, instead of being able to itemize and refund smaller amounts. For example, a Barstool costs $300. My client ordered 5, but changed the order to 4 before we delivered the products. The refund only lets me check the line for “Barstool Qty.5” and the total defaults to $1500. The price per item is not shown anywhere.

I can manually adjust the refund to $300, but the Qty. will still read 5 on the refund. This is awkward to explain, and inaccurate information for the client.