I want either to receive the item quickly, or a full refund.

[hinbut]

order number 12-07218-60321

It has been a long time since I placed an order, but the seller does not send the item.

I want either to receive the item quickly, or a full refund.

[disneyshopper]

Go to your Purchase History and locate the purchased item.  What is the last estimated delivery date?  You have up to 30 days past that date in order to file an Item Not Received case in ebay's Resolution Center, to get your money back.

If it is past the 30 day limit, you will need to log into Paypal's Resolution Center, and file an Item Not Received case there, as they allow up to 180 days from date of purchase to file, to get your money back.