Ebay seller advice on a dispute

[spoony]

Reet. I sold a sewing machine to a lad in bradford for £100 plus £25 p&p. It was in good nick before I sent it and was well packaged. He complained since it was delived that one on of the components has broken off during shipping. (sent it by Parcelforce) He's emailed pictures of damage and fair enough it looks broken like. Hes also suggesting I pay £59 for the part + £20 fitting for the replacement. Also whe I sent it, it was sent with cover upto £100.

What do I do? Any ideas?