I actually went straight to paypal and opened a dispute there because when I went to do something via ebay there was not the option I was looking for under Ask a question on the item page. Not sure if the questions/options have changed? The paypal resolution centre atleast had the option to open a case for "Not as described" - which is what I did. Should I/can I be escalating this to a claim?

If I 'have' to return this cap shouldn't I be using a tracked means which would mean Parcel Post or Registered letter if I could squash the cap like a pancake. Not sure of the costs. But I paid $6.99 for the cap and $6.00 for postage ($12.99). Would not make sense for me to have to fork out for the 'correct' return postage...(and no I don't just want to pop it in a street box).