You have only 45 days to open a dispute.
If the item has not arrived by Day 42 (or earlier if the seller is being difficult) go here:
http://ocsnext.ebay.ca/ocs/sr?st=1&query=My%20item%20hasn%27t%20arrived%20yet,%20what%20do%20I%20do?
and open a Dispute.
The link was found under the Help and Contact tab at the top of this page.
And oddly that link has changed since the last time I found it for a poster. Hmmmm.
In my experience, it takes 10 to 15 days for an item to arrive from Europe.
It takes 15 to 20 days for an item to arrive from North America.
It takes 20 to 30 days for an item to arrive from Asia.
Do not wait later than Day 42 from payment to open a Dispute.
And the first thing you will be told is to contact the seller. You've already done than so go on to Step Two.